Hi everyone. Long time no see. Finally got some T time today and it didn't go well. I was driving the truck today and going up a hill slowly. When I got near the top, I let the clutch out and instead of going into high, there was a clunk (not a bang) and it went into a neutral instead of high. I had no low, high, reverse, or brakes. The clunk felt like a normal shift but didn't work out that way.
After trailering it home (the ride of shame) I "just knew" it was the driveshaft or rear end. The engine would start and run perfect but not move anything. I jacked up the rear and put it on jack stands. With the engine running it wanted to turn the wheels so I thought I had a broken axle or maybe even a shattered axle key.
The previous owner told me it had brass thrust bearings in it but I doubted that story. Well long story short I'm now looking at what appears to be a perfectly fine stripped rear axle assembly and usable driveshaft. I found no chunks of metal and nothing to indicate that anything had broke.
While looking through the inspection cover if I hit the starter everything turns at the rear of the trans. I even put an extra u joint in the back of the crankshaft and tried to turn it but it certainly feels like the crank is ok.
The clutch fingers have a lot of slop in them but that would be normal for this worn out truck. Do you guys think I have a transmission/clutch issue?
Any help is appreciated!
When jacked up, I could turn both rear wheels but it felt like they weren't totally connected. They would turn opposite each other but sometimes not move for a second on the other side leading me to believe the was an axle issue. Could there be a problem inside the differential? It's still together and I can turn the axles by hand and see no problems, but I haven't taken it apart.
Oh and the seller was telling the truth - there was a nice shiny set of new brass thrust washers inside. I was hoping there was a pile of Babbitt in the bottom of the housings so I could have thrown it back together and been back on the road tonight.
Sorry to hear of the problems -- glad you and the truck are ok. Sometimes when the "no brakes" occur it can turn out really bad.
Did you stop using the standard cast iron parking brakes? Or do you have a lined 8 inch emergency brake shoes or external brakes? Or did you coast to a stop?
Please clarify what you mean by the sentence:
"Well long story short I'm now looking at what appears to be a perfectly fine stripped rear axle assembly and usable driveshaft. I found no chunks of metal and nothing to indicate that anything had broke."
Are you saying you have stripped down the rear axle -- meaning you disassembled the rear axle and found that all the parts are "perfectly fine" from the u-joint to the rear wheels? I'm just not sure what you mean by that statement.
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It's nice to hear from you too. I wish I didn't have so many hobbies because I miss my friends here when I'm off playing with other toys.
Luckily the rear had an older set of lined brakes and I also yanked the emergency brake lever as soon as I realized it started to go backwards. I had also started to slide over to jump out, but the truck stopped just fine. All of my T's have lined shoes but still I feel lucky.
What I've done so far is pull the rear and driveshaft as an assembly, then removed the driveshaft from the axle. I took the axle housings off the axle assembly but did not take apart the differential. The two axles are still together with the ring gear and differential.
I'm not sure I'm following you on everything, but it would be normal to have a little 'slop' in the differential. Something else that could make it look like there was slop is that when you turn one wheel, the driveshaft was turning some rather than the other wheel. You say you have it apart and can see the bronze thrust washers, but if it's apart, I would think you would see if you had a differential problem, so I am kinda confused. I assume the u-joint is intact? Pinion gear still tight and keyed to the drive shaft? As for the clutch fingers, If you are in any gear other than HIGH, they will be pretty loose. In HIGH, they should be clamped tight by the 'clutch shift' ring.
1. The crankshaft should not be a part of the problem. Even if the crankshaft was broken in two pieces the transmission brake drum would still stop the car. I.e. it will stop the brake drum, the u-joint, the drive shaft, the pinion, the ring gear, the rear axles, the rear axle key ways, the rear hubs and the rear wheels. Also the engine doesn't run very good if the crankshaft is broken.
2. This will be a lot easier if you have a second person helping you.
3. Be sure that you chock the wheels etc. so nothing moves and falls on anyone.
4. I’m sure your descriptions are clear to you -- but for some of us we are not certain what you mean.
5. I wish you had left the rear axle in the car -- as I think it would have made the trouble shooting easier. For future use – while the rear end and engine are still bolted into the car. With both rear wheels on the ground and chocked. Remove the floorboards. Look down at the U-joint housing. Behind the J-joint housing you should see a cap screw (part # 2578). Remove that cap screw. You should now be able to shine a flashlight in the hole and see the female part # 2573 of the U-joint. The Pin that holds that part of the U-joint to the drive shaft is installed/removed through that opening. Double check that the car is chocked and the switch is OFF. Place the car in high and have someone rotate the engine using the hand crank as you look in the opening where the cap screw was removed. If the crank is turned and the car is not going over the chocks then something is wrong. If you see the female part of the U-Joint rotating that indicates the problem is between that part and the rear wheels. If you do not see that part rotating it indicates the problem is towards the engine and is not that part. Just for future use at this point with your trouble shooting. Note in case the clutch was slipping badly – you could also step on the low speed or reverse pedal and with the person turning the engine hand crank you should see the same results.
6. Having already removed the rear axle assembly, and taken the drive shaft and axle housings off, I believe you will have to check things in a different manner. I assume that so far in the disassembly all the axle and drive shaft keyways appeared intact. Off the top of my head I cannot think of how you can apply a reasonable amount of torque to ensure that nothing is slipping with the rear axle disassembled. On the good side you should be able to visually inspect the keys and keyways and tell if something slipped or not.
7. Your guess that the babbit thrust washer was the culprit was a very logical assumption. Don’t beat yourself up for that one. I’m sure you will get it sorted out and many of us will learn through your experience as well.
8. If you have someone to train – now is a good time to invite them over. Good luck and keep us posted.
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I just took apart the differential; it appears fine and the gears are tight on the axles. The pinion appears to be still keyed and tight on the drive shaft and the u joint is in one piece as well. I'm waiting for my sister to get here to help me since I can't play with both ends of the driveshaft at the same time.
Wow. Everyone needs a sister like that.
I have a wife like that.
Craig, this is baffling. Hap's plan of action above sounds like the thing to do. Not sure how to do it with it apart, like he says. A sheared key on either end of either axle could cause what you describe. A sheared key on the pinion gear could cause what you describe. When you said 'crankshaft' above, I think you meant the hollow output shaft of the transmission. Is the hole in it still square? Is the u-joint shaft still square? It sounds like something like the these things are slipping.
With my sisters help we discovered that we can hold the u joint and turn the pinion gear.
Glad you got it figured out!
Oops, key in the pinion bearing. I've broken them before with similar symptoms.
I'm glad you got it figured out. You owe your sister a ride in the T at a minimum!
I always love the looks of your Mifflinburg truck.
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Got the rear back together with some delay due to having the race on in the garage...
Now if we hold the u joint, I can't turn the nut off. The shaft is turning with the nut but the u joint is being held fast. Do I have a broken shaft? Had trouble getting the u-joint pin out but I'll do that next. Thought we could just take the nut off the end and replace the key but maybe not.
U joint is off and the shaft out, but the shaft turns with the nut! It's like there's a separate inner shaft inside the bearing. Maybe I should stop for the night. Ugh
Well guess what? The driveshaft was broken inside the bearing sleeve. I put a wrench sideways under the pinion and tapped the broken end of the shaft out with the pinion and nut still on it.
The crazy thing is that the EXACT same thing happened to dad earlier this year (or late last year - can't remember) with his '29 Chevy. He was in a parade and let the clutch out when going around a turn and suddenly had nothing under his foot although the engine was still running. After we took out the driveshaft/rear end, we discovered it had twisted off the driveshaft.
Now all I have to do is figure out if I want to try and put my Jumbo in the truck or just get it back together this weekend.
That is one I had not seen or heard of yet! A bit over a year ago I sheared a pinion gear key. Similar result except the nut on the drive shaft and the U-joint were connected. It was the pinion gear that could slip with enough force. But the drive-shaft breaking inside the pinion bearing sleeve? Wow.
Drive carefully, and enjoy, W2
excellent thread that will help us diagnosis the same problem when it next occurs
As I was reading down, I said to myself, I bet he broke the drive shaft under the bearing race and it is tight enough to turn but will slip under pressure. Why did I know this?? It happened to me going down hill. When I found the problem, none of my T friends believed me that it broke in probably the strongest place on the shaft.
Actually, that is the weakest place in the shaft! As the torque of the engine is exerted on the driveshaft. The long shaft will twist slightly throughout it's length but the end with the pinion gear is rigid against the ring gear. Over a period of about 100 years this continual twisting will cause metal fatigue and eventually a small crack will occur. The car might be driven for a long time with that small crack and then when under pressure such as climbing a steep hill or applying the transmission brake, it will finally snap. This is the same as the broken crankshaft or axle shaft. It appears to happen suddenly, but might have been developing over a longer period until just the moment of high tension and snap.
I purchased my first Model T, a 26 Touring, from two teachers who almost stole it from the farmer they got it from.
They said the motor would run but the car wouldn't move, it just "shuddered" in position. So I didn't pay much for it.
When I got it home, I discovered it was missing an axle key in the left hand wheel!
It ran well after I replaced the key!
After a couple days of getting VERY dirty (this is one T I don't clean on purpose) the truck is back on the road. I didn't have a spare stripped driveshaft, just a couple complete shafts in housings. I wanted to install a new ring and pinion along with a shaft in good shape, so I threw in a used unit to get it moveable again. I'll rebuild the rear and driveshaft this winter and install them in the spring. At least that's the plan.... For now I wanted to keep working on the '27 and I can't do that if the truck is apart, in the way, and immobile.
Here's what the shaft looked like after I shortened it.
Also the sleeve was really ugly looking too.
I know this makes my sound somewhat paranoid but, this is why you should always go through the rear axle even if you were told it has be rebuilt. Unless you pull it apart there is no way to tell what was done, or not done. Your brakes depend on it.
That should say "I know this makes me."
Save that broken end of the driveshaft. It makes a good Knocker wheel puller. Screw the nut part way off and screw in the threaded end of the axle till it touches the end of the axle, jack up the other end of the axle and hit with hammer. Sometimes this method will work when the regular wheel puller won't. Try the regular puller first, using the knocker could cause damage to the axle. Use only if the other one won't work.
Craig, save the broken driveshaft also. It will be a good candidate for shortening for an auxiliary transmission. Someone would be glad to get it no doubt. Dave
R. S. Cruickshank, it happened to you going downhill.. that's scary! Did you have accessory brakes or did you save the day with the emergency brake?
Breaking under the sleeve seems strange? - George, do you have an opinion on the cause? Metal fatigue, but shouldn't the sleeve protect from fatigue right in the middle under it? At the rear edge of the sleeve would be more "natural", like where the pinion key slot ends?
Well, I guess the breaks occur where there's faults in the old Ford steel & fortunately Ford steel was mostly good quality.