I put a t5 tranny in my 54 behind the 235 6. After the car has warmed up the clutch shudders violently in reverse (reverse only) but works fine in the forward gears. I had the flywheel turned and a clutch and pressure plate built with the correct splines. The warmer the car gets the worse the clutch gets. What is up with this? Thanks for any and all input. Later, Dick
Tranny mount is new, engine mounts good. Why would this problem just occur in reverse and not the forward gears? Later, Dick
When in reverse the tail shaft would try and raise up,,make sure all bolts are tight in the mount. HRP
Drive shaft too long, possibly binding (closing the gap) the yoke on the tailshaft of the trans? Don't really know that being hot/cold would make much difference, though, so probably not.
Drive shaft is correct length. It has me baffled. Going out to my buddies shop today and pull the tranny and start looking. Thanks for your input. as I said before, when it is cold it works perfectly, but once it warms up it is horrible. Later, Dick
Check the part of the transmission that the throw out bearing slides back and forth on. I had one that was worn so badly that the bearing was not perpendicular to the arms on the pressure plate which caused a shake that you described but mine did it in fwd also. Worth a look. I found this problem aft changing about three pressure plates and clutches. ( 72 Nova )
Did you possibly omit a spring on the clutch fork? Really easy to check and try to hang one on it, it may help.
The clutch operates the exact same in forward as reverse, the clutch or engine have no idea what gear the Trans is in. What is different about reverse (exactly opposite) is the direction of load and forces thru the entire drive train all the way out to the wheels and the other way to the bell housing and engine mounts.
When you swapped the transmission, is it possible that you might have changed the driveshaft angle slightly? Might even want to look further back in the driveline and check rear springs, shackles and bushings.
I agree with 31Vicky and ClayMart, your problem is most likely in driveline mounts and or angles. That is, assuming you have a proper "Z bar" clutch linkage.
There's two things different about reverse. First is the direction, and second is the ratio. Reverse is much lower ratio than any forward gears, so the effect on the drivetrain is magnified. Get under the car and put a floor jack under the transmission, and lightly jack it up to see if the mount holds solid. Also open the hood and watch the engine as you attempt to back up and see how it reacts. If all else checks out good, then burn the clutch in a little. I've occasionally had clutches with new flywheel/pressure plates that just were grabby in 1st or reverse. I put the bumper against a solid pole, and slowly slip the clutch as I raise rpm's. Then drive it and see if it's stopped the chatter. Don't need to do much to burn it in, as you don't want to burn up the new setup.
T5 has its reverse gear ratio about .20 off from first. 3.35 first has a 3.15 rev 2.95 first has a 2.75 rev And all thre rest follow suit, off a little but close and not lower than first.
Alright, we have ruled out the tranny mount, the motor mount, throw out bearing, differential angle. We did find a bearing on the input shaft that was worn so just to be safe we are replacing it. This thing is driving me nuts (that's a short trip though). We had all the clutch parts out and every thing looks good, no oil on the flywheel, no silly wear patterns. It's kicking my ass. Later, Dick
Good catch on the output shaft bearing. Without first gear acting the same as reverse I wouldn't think you'd find any issue with the clutch. So now you know the symptoms are not a clutch issue. If it truly only does this in reverse, and no forward gears - it has to be related to the reversal of the torque thru the drive line to the wheels going backwards.
I used the 2 hole deal. A thought just hit me. I had a 54 Chevy clutch re splined to fit the t5 trans. the recommendation was to use an S-10 clutch but they were noticeably smaller than the stock clutch. Could that be the deal? Reaching for straws. Thanks for your input. Later, Dick
So, all righty then. After chasing this problem from one end to the other. I did what the folks I bought the adapter and tranny mount said to do in the first place. I replaced the clutch package that I had made up to the one they said to use. (the S-10 clutch package). It works like it is supposed to. Damn it, I should have listened in the first place instead of going through all this B.S. You'd think that being almost 73 years old you would learn to follow instructions. Later, Dick
LOL! Glad to hear you got it sorted out and back on the road. Though it would have been cool if one of our suggestions had fixed it... If you haven't learned to follow the instructions by the time you're 20 or 25, you're probably not going to learn it at 73...
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