What are the symptoms to look for when one suspects bad thrust washers? I understand if you are unsure if they have been replaced to go in there and physically see wether or not they were. I am asking, what are the symptoms to look for that leads one to the bad thrust washers? Such as, what is the car doing or not doing?
Thank you for your time,
When they go bad you can hear a ratcheting noise or a lack of forward motion.
If they're really bad, you may hear grinding or clunking sounds that seem to be from the transmission as they travel up the drive shaft tube. Often there's in-out movement of a rear wheel, especially on the right, that has wheel nuts hitting or scraping the brake shoes. A sign that's hard to miss is when a wheel locks up, or both wheels turn free with no connection to the foot brake.
The bad thing is that there can be no symptom one minute and the next minute, you could be trying to explain things to your Maker. Failure can be sudden and catastrophic.
Symptoms of bad thrust washers range from bad things to worse things, generally with a strong sense of panic.
It's not worth the risk. The differential is pretty easy to pull and take apart, it's just messy, and easy to replace the thrust washers. If you're good and diligent, you can have it done in an evening.
Always good to inspect the gears and pinion bearing as well. Since braking in a stock T is generally done in the transmission, the differential is critical!
I put new thrust washers in my '26 a couple of weeks ago. Prior to that it was very loud in the rear end , grinding sort of noise, and as mentioned by Steve , travelled up the drive shaft tube so it seemed to be underfoot. The right wheel had about 1/4 to 3/8 inch of in/out movement. On the drive before I pulled it down I felt the car surging and couldn't work out what was the problem. When I took the right wheel off I could see that the inside of the brake drum was scored, where it had been picking up the brake shoe. Took it out last weekend for a hundred mile drive.. seems OK now.
I drive pretty slow and my 1919 Touring made no unusual noises at all but the oil in the rear end was a dull gray color which ended up being ground up Babbitt thrust washers. Upon removing the rear hubs the edges of the brake bands had ground a groove in the wall of the hubs from all the internals shifting back and forth on turns. After breaking down the rear end there was no Babbitt where it should be and 8-10 pieces about the size of a pea in the bottom of the differential.
Sometimes, especially if it is the left washer that fails, the first symptom is the fence post or tree in the middle of your radiator.
Seriously, any looseness, side play beyond a very small reasonable amount (almost none), binding when turned by hand, clunking, knocking when braking, or brownish or glittering colors in the differential oil, are indicators of some potentially dangerous failure on the horizon.
The model T braking system was very good back when the cars were new, traffic was mostly light, and speeds were low. Today, the system is adequate IF it is properly maintained, and special care is taken to allow for its limitations. For a basically stock model T, the rear end is a centerpiece to the braking system. There are several things that can break or fail resulting in a sudden and major loss of braking ability. If there is any doubt in the condition of the rear end, it should be removed and thoroughly checked and repaired.
If one is young and healthy, and has a good understanding of how to do it? The thrust washers can be replaced in a very few hours. However, more than they should be checked inside. Axles should be cleaned, inspected. Pinion bearings looked at and adjusted carefully. Along with a few other things. The hidden danger is that fifty years ago, it was considered okay to rebuild a rear end and use the old Babbitt thrust washers if they looked to be in good condition. Many older restorations have nice running tight axles with those "land mines" hiding inside. The Babbitt is a soft metal, good for bearings. However the rear axle is subjected to several contaminants which along with age break down the Babbitt, leaving them subject to sudden failure.
If one has any doubts about the rear end? They should find a good time, soon. And fix it right. That fence post down the road is counting on you.
Axle end play. ANY end play like Wayne tells about right above.
The rear end in my 18 had been "worked on" 30 years ago and never driven again until last fall.
It only took 5-7 miles for one of the original thrust washers to fall completely to chunks.
I don't suppose they knew of the danger back then.
My son and I were lucky and we made it up my hill without incident on its last drive last year.
I even backed in into the shed. I was able to re-use the radius rods and grease cups.
A camera inside the fill plug hole might be able to see the RH thrust washer.
Would you please check them Willis?
I plan on checking them very soon. Thank you for mentioning the camera in the hole. I have one and will try that after I go through the other items on the checklist. I'm really not expecting to see anything but, hey, I have the thing why not use it!
Thanks to all whom responded,
Symptoms of bad thrust washers? If your lucky ,sore feet from walking home. Really its not tough to tear it down and check it out. Even I did it.
I am trying to gather some information pertaining to symptoms on what to look/listen for. As far as noises, I haven't heard anything. It is good to know what to look/listen for.
I wish someone had warned me about the fan blades when I first got the car. That a blade could fly off at anytime! Thankfully, did not lose my head, fingers or radiator in the process! That was nearly 10 years ago and in all this time I have only put about 1,000 miles on the car!
Get a small sample of the diff oil, if it looks silvery then there is potential problem. Lift the rear of the car and with emergency brake off, check for in/out motion on either wheel.
If you get positive results on either test, you really should strip the axle.
As Hal says, sometimes there are no symptoms. Failure can come without warning.
Let us know how the camera works out.
After I had purchased my 25 a few summers ago I knew that a differential inspection needed to be done, but wanted to get at least a few drives in before Fall. A week or two before the initial inspection I went for one last ride. As I was backing down our sloping driveway and I turned to the left at the end, I heard and felt a "POP". I was able to pull it back up the driveway and into the garage. I was very lucky that I wasn't out on the road.
It turned out to be a badly chipped pinion tooth. In this case caused by excessive ring an pinion clearance due to old and very worn babbitt thrust washers. Unfortunately the thrust washers were just the tip of the iceberg, so please do a complete inspection, repair what is needed and don't cut corners.
The last drive before I rebuilt my rear axle,we delivered christmas gifts to some friends children. On the way home I was hearing clunk every so often. It would jerk eveytime I heard the clunk. I knew it needed rebuilt because the seals leaked gear lube into rear drums. The drums had wear marks where the axles moved back and forth. When I tore it down there was no pin found in the U-joint. I think the clunk was the pinion gear slipping on the ring gear. Dive in and git er done. You wont regret it. Mine is quieter and faster after rebuild.
No doubt, there are plenty of symptoms for "Bad thrust washers". It's the babbitt thrust washers that are still intact, but can let go at any moment, that are the problem and for that, there are no symptoms. Someone once posted a picture on here of some they had removed from a rear end that were still totally intact. No chunks missing around the edge. No excessive wear. I seriously doubt there would have been anything to see in the oil, but the fact was they were still Babbitt and most of us know how easily they can crumble. Not worth the risk.
Some are like this...
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Ive gone through 2 rear axels and both had good original thrust washers. Better off doing it sooner than later, depends on how much you value yourself and the safety of people around you. Its probably one of the most important things to check on an unknown T. Make sure you go through the whole rear axel and also the driveshaft to make sure everything is in good order.
I'm about mid-teardown on my rear axle and while there was zero end play on each wheel, there's also no thrust washer visible at all through the pinion hole. It should be interesting to see what, if anything is left of the washer and if it's gone what could be preventing that end play.
>>>The bad thing is that there can be no symptom one minute and the next minute, you could be trying to explain things to your Maker.<<<
I've known a couple people whose first symptom of a heart problem was keeling over dead. First symptom.
(Message edited by jesselashcraft on July 16, 2017)
Sudden loss of your brakes. Unless you take the axle apart it's impossible to know what condition it's in. Much more than the thrust washers usually needs to be replaced.