Front differential fluid leak causes. They must be sealed as well.
Front differential fluid leak causes Now about 2 weeks later the front drive shaft / pinion seal is spewing oil/fluid. This is the most common and easily spotted symptom of a bad pinion seal. Mar 29, 2012 · Front Pinion Leaking - Cause? At about 40k miles I took my truck to the dealer for a recalland they recommended having the Front and Rear differential fluids changed. Keep your Dec 23, 2016 · Hey Guys, newbie here, my first post. Differential Fluid Leak Service. Left side carrier bearing bad. Mine did a similar thing, but I’m running an aftermarket front cover and filled the fluid up until it came out the fill hole. Going to see the manager on Friday, but if I can't get them to fix I will have to do it. Oct 27, 2022 · Cars with four-wheel drive have both, which means you’re prone to a rear differential leak as well as front differential leaks. I managed to take a photo between the crossmember and the diff. Differential tubes convey the differential fluid from the differential to the axle, a necessary process to sustain optimal lubrication levels around the moving axle parts. I've looked it over and don't see any cracks. Strange Noises and Vibrations from the Rear of Your Vehicle. Nov 2, 2023 · Occasionally you should take a peak under the diff cover and check for differential fluid leak. In this article, we will explore the causes of front differential leaks, how to diagnose the problem, and the steps you can take to fix it. May 19, 2010 · While changing my oil today, I noticed the back of my front diff was wet. Why is my rear differential leaking: Causes of Rear Differential Leaks Nov 4, 2021 · Front-wheel drive cars have a front-end differential (sometimes called a transaxle). The leaking oil can end up on the ground surface. Aug 8, 2017 · the reason i ask is even with a bad inner seal usually the new style dust seal will retain the fluid replacing inner seals is a but of a challenge, since the axle shaft have to come out the good news is if you are in 2 wheel drive and confirm your front axle is not locked then you don't have to fix this anytime soon Jan 19, 2020 · After a bit of Holiday wheeling in North Georgia and Hurricane Creek in North Carolina, and all those highway miles the front diff on the 2015 Jeep JK dev Dec 12, 2020 · A few months ago, I was servicing my differential fluid on my 2015 Subaru Outback. Our 2008 Highlander was in to the dealer for its 85K mile service in October. Find out what is really leaking - most likely the engine oil from a failed oil filter housing gasket. Big job? p. so I said ok. Regular inspections of your rear differential fluid can prevent costly repairs and ensure a smooth driving experience. Stay informed about Dec 21, 2021 · Congratulations on the trail damage - that's why you have armor. It seems to be coming from the between the two halves, so I figure it's a gasket Jan 30, 2022 · With the problem in the front diff, to not have it in 2H says the front drive shaft and axle shafts aren't turning in 2H. Learn the importance of color, clarity, and odor assessments, alongside maintenance recommendations for fluid changes every 30,000 to 60,000 miles. 00 TORQUE CONVETER PRESSURE SWITCH (LEAKING) $310. Nov 21, 2011 · Mine is leaking on the passenger side were the axle shaft bolts to the front diff. I checked the oil level in the differential and it is fine. Apr 4, 2018 · I assume, when they replaced the rear diff fluid, they finger tightened the bottom plug and forgot to torque it. I don't see that there's a way short of "drain and measure" to see how much fluid is in there. With constant use of a vehicle, these tubes are subjected to wear and tear; hence leaking occurs. Sep 1, 2023 · If you suspect a front differential leak, it’s important to address the issue as soon as possible to prevent further damage to your vehicle. Jan 16, 2023 · It looks like it's leaking at the front of the diff. This comprehensive guide covers the significance of maintaining fluid levels, choosing between conventional and synthetic options, and the tools you'll need. I got a quote from a local mechanic and it needs to be fixed to pass inspection. A leaking axle seal may be covered by your vehicle’s Powertrain Warranty, so check your car’s brochure to see if this is the case. Replaced front differential assembly and one time use parts. Confirmed it's coming from my front diff. I looked where the axles go into the diff. Oct 9, 2024 · Fluid Leaks: Puddles of oil under your vehicle can point to a leak in the rear differential. So, if you see oil leaking and you notice that it has a distinctive odor, that leak could be a differential fluid leak. Puddles of oil on your driveway are usually one of the earliest signs of an axle seal Aug 4, 2010 · Seal the holes where they go into the front differential. Jun 11, 2013 · Axle Seal (knuckle seal), Large outer seal (1 PER SIDE) FORD F81Z-3254-CB, SKF 28600 Dust Seal, Small inner seal (1 PER SIDE) FORD F81Z-1S175-HCA, NATIONAL 710413 Axle, Needle Bearing, Front (if needed) FORD C6TZ-3123-A, NAPA B2110 Axle Shaft, Outboard End (if needed) FORD 4C3Z-3B387-AA Axle, U-Joint, Front (if needed) FORD F81Z-3249-AA Sep 8, 2014 · My front diff has had a slow leak for quite some time. Also, I’ve heard ( but not confirmed) that the actual fill spec is 1/2 inch below the fill hole. I guess it depends on how much it's leaking as to how big of an issue it is. What does a noisy differential sound Aug 5, 2012 · 509000 Axle Concerns: Content: Front & Rear Differential Noise, Minor Oil Seal Leak & Debris in Oil. I did notice it after using 4x4 a couple of time last week but not sure why that would cause it. Sep 27, 2021 · Had some time to look a little closer at the leak. Fluid only leaked when any of the 4WD modes were engaged. The most frequent sign of a problem with the differential output seal is a front differential leak. When I got the truck home I discovered the Jul 4, 2008 · The differential housing is dry on the top, so it's not an oil leak running down or anything, I was just wondering what you guys thought, and how hard it would be to replace the seal in the differential, and if I had to go to a dealership, which I probably will, being that I don't necessarily feel comfortable ripping the housing apart, how much Dec 13, 2020 · Then your differential is leaking. I'm worried I may have caused the problem pulling a tree stump with a tow rope after a couple failed attempts. Discoloration : If the fluid appears dark, gritty, or has a burnt smell, it may need replacement. If it's low or dirty, it can lead to overheating Jan 28, 2009 · I stopped for gas and noticed some fluid leaking from the front of the truck. 5 liter Mechanic's Assistant: Are you fixing your Nov 26, 2021 · Stox, do you have an aftermarket front diff cover? The fill hole on some covers is know to be at a higher level. Dec 7, 2017 · I just got to my campspot in Utah for the night, after driving 1,600 miles from Alabama. Differential fluid leak (if your vehicle has a rear differential) Black. Customer: Front differential housing leaking fluid between transmission Mechanic's Assistant: Can you actually see the leak? And is the fluid itself bright red, or is it dirty? Customer: gear oil Mechanic's Assistant: What is the model/year of your Subaru? Customer: 2015 Subaru Forester 2. Oct 3, 2023 · The front and rear differential fluid levels on both of my E83’s were ok at 160+k miles when I refilled them. Regular checks every 5,000 to 15,000 miles can Feb 27, 2023 · As a differential ages, the internal components will wear down and eventually fail. Front is the front diff, then gear case, then rear extension housing for the 4WD bitsall full of gear oil and/or transmission fluid if it's an auto Pull the transmission, disassemble the front diff and reassemble with anaerobic sealant. A: In front-wheel-drive vehicles, this often indicates a transmission fluid leak since the differential is typically integrated into the transmission. I popped the hood and there is diff fluid all over the place around the top of the vent tube. It's not a drip just yet, but was wondering where it's leaking if the Blue Devil I just added doesn't seem to work. Oct 1, 2024 · Learn how to properly fill your front differential fluid to enhance vehicle performance and prevent costly repairs. See full list on motorvehiclehq. Removed front differential assembly. . However, the axle seal can wear out or get damaged over time, and this can cause it to leak. The Front Differential Leaks Oil. Differential fluid is located in the differential tubes, which convey the fluid from a differential to an axle. 10 are the likely choices), then you can go the junkyard and find the same one Jan 5, 2011 · The gear oil is a bit thicker at those temps, so when running 4HI, its sloshing around more in the diff and more likely to spit out fluid. Oct 8, 2024 · Fluid Replacement: If differential fluid is contaminated or low, replace it by draining the old fluid, filling with the appropriate new fluid, and ensuring all seals are tight to prevent leaks. Passenger (RH) Side Drive Shaft Aug 25, 2021 · Be keen when inspecting any leaks towards either of your tires. You barely notice its there. Check your car’s manual for instructions on how to do this properly. This comprehensive guide covers the importance of lubrication, signs of low fluid, and step-by-step instructions for adding new fluid. One is for the AT and the other is for the front diff. I just checked the level again, and it really hasn't lost much fluid. Apr 15, 2021 · My rear axle seal was leaking and had them replaced ($455) not realizing what had happened. This repair does NOT require transfer assembly removal from the vehicle. Sometimes, you will only notice it if you turn on the engine and allow it to run. 2. My regular shop. It is crucial to transport differential fluid from the differential to the axle because damage may result if the differential fluid level falls too low near the axle’s moving parts. There is a fluid leak at the front of the rear differential and appears to be originating from the area where the drive shaft enters the rear differential. (42,000 miles) Unfortunately, I believe that this only added insult to injury because I observed that the pinion nut was overtightened with an impact wrench. Oct 5, 2024 · Discover how to ensure your vehicle's performance by properly adding front differential fluid. Jan 4, 2016 · Depending on the location of the seal and the severity of the leak, a bad seal may sometimes cause the differential or transmission fluid to leak out entirely. ly/JoinMaxCarGuyIn this video we gonna talk about the causes of the front differential leaking and ways to fix the issue. I drained it all and filled back to proper level. com Oct 28, 2023 · A front differential leak can be caused by a bunch of things—from tiny missteps like overfilling to more obvious issues like damage from impact. Visit Us 20540 88 Ave Suite 102, Langley Twp, BC V1M 2Y6 Apr 19, 2010 · Breather Hose constantly comes off at front differential So not only do I have oil coming out of the top of the breather tube, but the connector itself keeps coming off of the front differential. Jun 18, 2012 · Either way, if it's a very small leak you don't have to do it immediately, but keep an eye on it to make sure it doesn't get worse. Did all my homework to make sure I had it all right. A deficit of differential fluid at the axle could prove detrimental, inflicting lasting harm. Oil will be black in color. They must be sealed as well. In addition, the axle seal can wear out over time, which can cause it to leak. There seems to be fluid leaking out (slowly) from where the axle goes into the diff. They topped-up the fluid and said leave it until the 90K service when they would check it again. They have a 12 month 12 K warranty but I have burned thru 30K so they won't fix it without $$$. Inspect the differential housing and driveshaft for fresh differential oil residue. A leak in the front differential causes a decrease in lubrication and can lead to excessive friction and heat buildup. I changed the fluid in Sept when I had to change a pinion seal with only normal winter driving since then. Here’s a non-exhaustive list of the most common leaks. Finally got it open and threads were damaged. Leaks in Differential Tubes. Cars with four-wheel drive have both, which means you’re prone to a rear differential leak as well as front differential leaks. I suppose the fact that it was still dripping means it's at least not quite dry. Q: How long can you drive with a rear differential leak? Mar 27, 2018 · If you jacked up just one side and filled the diff, then yeah, that extra fluid is just from being a little over-filled. This article explores the benefits of conventional versus synthetic oils, and offers a detailed guide on changing the fluid, including essential tools and disposal tips. That's it as far as I know, but again, I've never actually done it. I had a dirt dauber build a nest in my tranny breather tube (my F-250 truck) and fluid was weeping out the dipstick tube. This comprehensive guide covers the importance of maintaining correct fluid levels and types, along with common mistakes to avoid, such as overfilling and using the wrong fluid. I just changed my front differential fluid (Dana 60)for the first time since i've owned this truck. Differential oil under your car Brake fluid leak; Amber. Brake fluid leak; Differential fluid leak (if your vehicle has a rear differential) Dark Brown. Sep 27, 2017 · AXLE - FRONT - FRONT DRIVE AXLE FLUID LEAK FROM VENT [*****]Publication Date: NOVEMBER 6, 1998[/COLOR] LIGHT TRUCK: 1990-1997 AEROSTAR ISSUE: Front drive axle fluid may leak out of the vent under some driving modes on some vehicles. 25 or 9. If you’re concerned that your axle seal might be leaking, here are a few things to look out for: Oil stains on your driveway. Probably over-torqued by whoever did service last. So I get home today and pull the lower plug and fluid comes gushing out, not dripping. Oil Oct 18, 2021 · I have a 2017 Colorado with 2. In doing research I found overfilling could cause. Bad Differential Side Seals May 22, 2023 · Had dealership take a look after another shop confirmed front differential and transmission leak, these were the results: Technicians findings: *Transmission Concern: FRONT & BACK CHAIN PUMP COVER RESEAL (leaking) $1,066. If it has been a while since you changed the differential fluid and there aren’t any leaks, you should drain the oil before you pour the new fluid. I drained the fluid and found metal shavings in the oil and on the drain plug, but not chunks of metal. it looked wet around the transfer case. Usually, these sizable leaks will also leave a considerable amount of differential fluid on the bottom of the differential. Consider inspecting/cleaning the front diff vent, and using some brake clean spray to get into the area around the CV axle where it enters the housing at Oct 24, 2023 · Not all of the differential fluid that seeps or drips out of the diff remains on its housing. When I went to add the new fluid (Lucas 75W-140) I got just over 3 quarts and the diff fluid started coming back out the plug hole. Dec 11, 2018 · The most common cause of a leaking axle seal is improper axle installation or removal but the axle seal can also wear out over time. Removed carrier assembly found right side bearing to be bad, bear race spun in the housing assembly. Common Mistakes to Avoid: Avoid overfilling the differential and using the incorrect type of fluid to maintain vehicle performance and prevent potential damage. How to Prevent Top Causes of Front Differential Symptoms. You can check the fluid level in the diff periodically by removing the fill plug and sticking your finger in there, if the fluid is level with the hole or just below it, you're fine. When axle seals fail on straight axles that span the entire distance between the wheels, you may see grease or oil on the inside sidewalls of your tires. Anyone experience this on their 14 gen? Just hoping it’s not months for parts! Sep 20, 2010 · My Jeep is leaking fluid out of the front diff. This seal helps to keep the differential fluid from leaking out of the axle. When I went to open the front diff overflow plug, it was EXTREMELY torqued down. Norlang Auto Repair Langley. Jul 24, 2023 · 5. Jan 1, 2012 · That is a big difference, that much could be causing your problem for sure, you may have to get a pair of tires because that much difference could easily ruin a rear locking diff, the front is open and you will get away with it minus the fluid overflow problem for a long time, but this can and will cause damage over a long period Nov 1, 2024 · Ensure your vehicle runs smoothly by learning how to check your front differential fluid. May 29, 2008 · Just wondering what would cause fluid to out of nowhere start leaking out of my front diff vent tube. Oh, and they quoted me $1,800 to reseal the differential! Nov 10, 2024 · Become a Sponsor - https://bit. Took a lot of force to open with breaker bar. 00 Axle Seal: RIGHT FRONT AXLE SEAL AND O-RING (LEAKING) $411. Jan 8, 2023 · The list below includes some of the warning signs of a front differential leak. There are two key signs that your differential is failing: leaks and noise. I put in new fluid and will have someone else fix the leak. I noticed my front diff breathers appear to be leaking. Seal them well. But why will this fluid leak from the differential? There are many possible reasons for a leaking rear differential: 1. So it is best to check and replace the axle seal when damaged. The tube does have the plastic vent in it. When a seal gets too old or damaged to maintain its integrity, lubricant will seep out of the differential and drip on the pavement. But other issues can cause fluid to come out those vents too. Differential Tube Leaks. to show the leak seeping. 73 or 4. But as you drive, the leak becomes obvious and splashes behind the tires. Mar 29, 2023 · What causes a differential to fail? A number of factors can cause a differential to start failing or break entirely, many of which are avoidable. com seats with charger console lid, XPEL Prime XR Plus 70% nanoceramic tint, Builtright rear seat MOLLE racks, bed racks and dash rack, integrated WeBoost Drive Reach, Fab Fours Black Elite front and rear bumpers with "custom" aftercooler Jul 9, 2013 · If you have water in your diff and the fluid level is high, this will cause a lot of fluid to leak into the tube during a repair such as an axle u-joint. Gain Jul 17, 2007 · This is a 4EAT phase I. I can't imagine why the breather would be weeping other than maybe it's constricted somehow. A significant amount of differential fluid leaking out will cause moving parts to grind together and cause damage. Some leaks are annoying but fixable, especially if you’ve been bitten by the DIY bug. This comprehensive guide highlights the signs of deteriorating fluid—like unusual noises and leaks—while offering crucial inspection tips. Differential fluid leak. Not sure the best way to do this, but it must be done. The fluid glows fairly brightly when a blacklight illuminates it. How big of a problem is this? How easy is it to fix? Thanks. I'll try to find how much he charges to fix it if you give me a bit. Rear fluid done no problem. If the seals deteriorate or dry out, the axle shafts will leak fluid. I thought there was a way to ziptie it to something to keep this from happening, but I havent found anything near to do this. Those of you with correct-wheel-drive (or 4WD/AWD!) may notice some odd puddles on the driveway at the rear of your vehicle, or some oily grunge in its under Aug 31, 2024 · Discover how to identify bad differential fluid and maintain your vehicle for peak performance. after the fluid has entered the tube and get mixed with the dirt, rust, and dust that is in there, it will seep out for months before it stops. I am guessing they overfilled it since it had never leaked before. Dec 15, 2018 · It was just a couple days ago that I noticed my front diff was leaking. Looks like it's leaking right around the driveshaft seal. 1. If the differential fluid is not changed on schedule or if you drive around with a low differential fluid level, it will wear down faster. Low or Contaminated Fluid: Differential fluid lubricates and cools the components. It could be a differential gear oil leak at the axle seals or brake fluid leaking from a faulty brake system. Finally, remove the driveshaft from the transfer case to the front differential, and seal up the holes left by it's removal. I last changed the fluid 20k miles ago, and this is the first time it's leaked. You can expect differential fluid leaks from the differential casing when it does. Differential oil under your car. 25") and what the gear ratio is (3. Oct 9, 2022 · 5. Oct 28, 2023 · A front differential leak can be caused by a bunch of things—from tiny missteps like overfilling to more obvious issues like damage from impact. The truck did this before right after I changed the diff fluid for the first time. Worn Out Bearings: Over time, the bearings in the differential can wear out, leading to noises like humming or grinding, and potentially causing misalignment of gears. Pinion bearings bad. :frown2: Jun 25, 2009 · 2003 Ford Ranger FX4 Level II. Dec 30, 2015 · What Causes an Axle Seal Leak? The most common cause of a leaking axle seal is improper axle installation or removal. I thought it was weird that they would suggest a fluid change when there's possibly a leak?! Went below to have a look. This friction can cause vibrations to manifest as shaking or trembling sensations throughout your car. Symptoms of a Failed Differential. Photos were taken while I was behind the driver's side front tire with the camera pointing towards passenger side. May 7, 2021 · Attached three photos of front differential. Over time, this gasket will wear out. Over time, this seal can become worn or damaged, which will cause a leak in your differential. Learn about essential tools, recommended fluid types, and maintenance tips to keep your differential running smoothly. The main purpose is to keep the internal case pressure the same as atmospheric so the seals don't get pushed out. This gasket is usually made of rubber or silicon. The primary cause of a leaking axle is an improper installation or poor maintenance of an axle seal. Differential fluid leak (if your vehicle has a rear differential) The Most Common Leaks. Another common front and rear axle seal leak symptom is reddish fluid behind the tires. Concern: Noise (Whine or humming) from the front or rear differential. Oct 22, 2024 · Step-by-Step Fluid Change Process: Follow a clear procedure for changing both front and rear differential fluids, including draining old fluid, adding new fluid, and checking for leaks. May 4, 2022 · Thus far: RF component speakers and 8" sub in Ford enclosure with RF amp, full cab Dynamat, Leatherseats. The only other fluid at the wheel end of a straight axle vehicle that could leak would likely be brake fluid, so basic inspection can usually tell you what type of fluid has been leaking. Low differential fluid level May 13, 2013 · The entire transmission is full of fluid - many quarts of it, so yes it's full of fluid from front to rear. It has the same problem with a seal that needs replaced. Minimum fluid drain and full of metal. ACTION: The axle seal is located at the end of the axle, where it meets the differential. There are two main ways to check for a leaking differential. Those two s-shape snake like hoses at the topish leftish of the pic are the vent hoses. The differential fluid must be transported from the differential to the axle through differential tubes. As pointed out above, a leaking axle seal drips slowly when the car is parked. Therefore there is some sort of hub disconnect (or maybe at the diff, but not familiar with that sort of setup) rather than having a live axle where it is connected all the time. You need to find out what size diff you have (8. Discover the best practices to ensure optimal lubrication, heat dissipation, and longevity for your Jan 24, 2015 · So, my real question/ issue is this. What Are The Signs I Have A Front Diff Leak/ A Differential Issue? The differential is a vital component to your vehicle. Well, now my front passenger side is seeping. 😉 May 16, 2022 · Dropped my truck today at the dealer for leaking differential fluid where the transfer case driveline enters the front differential. 00 Dec 20, 2022 · However, you may also notice that your vehicle handles differently when taking sharp turns – this could indicate an imbalance in pressure between tires due to a lack of lubrication from the leaking fluid. I was reading on this and it sounds like it can be caused by overfilling, or water contamination. Actually, I noticed it only because I was replacing my AC idler pulley for the second time in a month - having replaced it on Th Causes Of A Leaking Axle Seal. 8L Duramax and the front axle has been leaking differential fluid for about a week (pictured). A normal well-lubricated rear axle runs smooth and silently. I've been leaking fluid for weeks. #1 – Differential Housing Seal Leak The differential housing seal prevents oil from escaping at the mating surfaces between sections. If you’ve got a bad seal or your differential gasket is going bad, it’s best to catch it before your gears eat themselves. I did notice a fluid stain in my driveway front right side. Aug 20, 2024 · I discovered the front pinion seal leaking and had the dealer replace it under warranty. The stealership "fixed" it in February and it is leaking again. Bad Differential Gasket. Dec 3, 2013 · Yingpin, Your leaks are from the axle seals on both sides. If you slightly overfill the front diff, it can spit some fluid out the breather. Follow our step-by-step instructions to inspect fluid quality and detect potential issues. There's a gray colored fluid leaking out between the where the passenger side tube housing bolts to the case. May 8, 2024 · The following are several potential causes of a leaking front differential. Checking differential fluid should really only be done by a trained mechanic, but you can look May 17, 2017 · Was told that my front diff fluid needs to be changed, and that it looks like there might be a leak. The way that you filled the front diff were the fluid level is level with the bottom of the fill plug is basically common practice and you caused no harm by doing it that way. Sep 6, 2023 · A front diff leak needs to be fixed urgently, as a lack of gear oil lubrication on your car's differentials can cause serious problems. They mentioned the front differential had a very small fluid leak. Regular checks can prevent costly repairs and enhance Aug 29, 2022 · Differential Leak Stop. This can cause problems with the gears and bearings, which can lead to costly repairs. For Auto Repair Call Us (604)888-8681. What type of repair and approx cost to have this rectified. If your differential has a drain plug, you’ll just have to remove the fill-hole plug at the top and unscrew the plug. DO NOT REPLACE the transfer assembly. A minor oil leak may be evident with possible debris in oil. About a second after I added to the fill hole, it started coming out the oil fill level hole. Effects Of A Leaking Axle Seal Jul 17, 2021 · Hey guys, i have rav4 2010 v6 limited, i noticed an oil leaking between the front differential and transmission, we replaced the gasket but the the problem is persisted , note that it's leaking only when the engine is heated, can someone help me please If fluid is leaking from the front passenger (RH) side of the transfer assembly, refer to the information in this bulletin. A major rear differential leak can deposit oil spots underneath your vehicle. and nothing is leaking there. Learn to identify signs that indicate it’s time for a change, such as unusual noises, leaks, or dark fluid. s. Proactive Maintenance: Staying proactive about differential fluid maintenance enhances your vehicle’s handling and can prevent costly repairs due to Sep 18, 2024 · Discover the crucial role of rear differential fluid in your vehicle's performance and safety. Axle shaft pops out Apr 25, 2008 · Sometimes dirt/mud will get in that area and cause the seal to leak, and sometimes a clogged diff vent will cause pressure build up in the front diff, forcing a slight leak at an axle seal. 3. Cause: The casing black paint /sealer degrades, detaches and contaminates the oil. Differential oil typically has a distinctive smell. A leaky seal should be addressed as soon as possible, as a transmission or differential low on fluid because of a leak can quickly become damaged by overheating. This may be caused by the design of the vent. Oct 24, 2022 · “Removed front cover from differential assembly. Lack of oil: Even a tiny leak can mean the components in your differential end up grinding against each other. The fluid leak is NOT caused by the dust seal shown in Figure 1. tkqyv qaicut lfezgv kggnfckok dugcc ymfn suxzq kxyz sgs odqjgu