The Stovebolt Site Forums The Shop Area Driveline Steering wheel vibrates

I finally am finished with some driveline work. I am doing a 56 Apache 235 w/3spd. I replaced both front and rear ujoints as well as the transmission slip yoke. When I first drove it and got over about 25mph I a felt a good bit of vibration in the steering wheel, but could really feel it. It did not vibrate before I replaced those joints. (The joints were really worn, btw. Especially the front one). As I drove it more the vibration lessened. Now I primarily feel it when I de-accelerate. The vibrating shows up primarily by the steering wheel vibrating a bit. But you can feel it in the cab. So I am just chalking it up to all of these new parts needing to work themselves together and wear in a bit. I hope that the vibrating will stop over time. Am I under-reacting here? Is there anything else I should be checking?

all 4 motor mounts, wheel balance, front end alignment

Bill

Wheel balance and alignment is a great idea. I recently replaced the motor mounts. Thanks for the tip.

Don't expect the vibration to go away over time. If it's there it's there.

Alignment will not correct a vibration problem. Just from the description, it sounds like you may have loose lug nuts, possibly with egged out wheel stud holes in the wheel.

As I understand it, your vibration problem started after replacing the U joints, correct? So maybe something with that process caused the problem. I am not familiar with your driveline but could the relationship between the front and rear U joints have changed?

As stated above,the front and rear joints need to be "Indexed"
I.E. if the cross of one is not indexed with the other a vibration ensues.
If the front is at9,12,3,and 6 o,clock,the rear one HAS to be the Same.
This is with a slip yoke on the shaft.
steve sr.

The vibration definitely started after replacing the ujoints. My driveline has 2 joints. I don't quite understand what you mean by indexing. How do I know if they are indexed? Since I don't even understand the question then the only they they would be indexed is if I randomly did it. Thanks for any info on that.

Ray, To index the u joints, The grease fitting must be facing the same direction and lined up the same on both ends. That will make them indexed.

I do remember (I am at work now but will check wehn I get home) that when I installed them that I positioned the fitting so that it would be easy to access when I put it together. So I pointed both of them towards the driveshaft on both the front and rear joints. But I will go back and look and see if they are both facing either down or up as well. But to that point, is having them both pointing inwards towards the driveshaft considered aligned?

That's OK as long as the grease fittings both point the same.

Rereading your 1st post I think you may have a tire out of balance situation. What tires are you using? Biasply or radial?

Indexing on a single piece drive shaft is not an issue. The yokes are welded in the proper
relationship with each other and can’t be changed. Indexing becomes a concern when you
have a splined slip joint between multi-section drive shafts or when you are fabricating a
new drive shaft.
Where a grease fitting is has nothing to do with it either, put them wherever you want.
Vibration from the drive shaft would be felt in the seat of your pants, if it’s in the steering
wheel, then it’s got something to do with the front end as some of the guys have already
pointed out.
Denny Graham
Sandwich, IL

what Denny says - indexing can't be messed up on your 56 unless you cut the yoke ends off the drive shaft, and the grease fittings can be any which way

Bill

Wow am I learning a lot here. Who knew so much could be happening? It's really an education for me and I thank everybody for the dialog. I did recently (before I began the ujoint project) replace the tie rod ends and the tires are kind of old but I do not remember the front end shaking before I replaced the ujoints, so that is why I attributed the shaking to that. I have some new (bias ply, 6.70-15)tires on order. So when I put them on I will balance wheels and check the alignment and see if that solves the vibrating. Thanks again.

Sorry to bust your bubble Ray, but don't be surprised if you don't get a lot of "vibration,
wheel hop, or steering wonder" from the bias ply tires. They weren't all that good back in
the day when that was all the manufacturers made and now a days most are even worse.
If I was to recommend a tire it would be a radial tire.
The brand new Power King Super Highway bias plys that I put on my 3600 truck lasted
about a thousand miles before I pulled them off and stacked them in the corner. Had them
rebalanced three times, had them road force balanced the last time and I still had
problems with them. The front end would vibrate so bad the first 5 or 10 miles I drove it
in the morning that I thought it was gonna shake the sheet metal right off the frame and
they didn't track all that good either.
The Cooper radials are as smooth as silk and the truck drives hands off at highway
speeds.

Denny Graham
Sandwich, IL

Denny, I took the truck into a shop today to have the exhaust system replaced. I mentioned the vibrating to the shop owner and he said almost the exact same thing that you did. Amazing. Anyway, I had radials on my 59 Apache once and I loved how they rode while I was driving. But trying to turn them when I was stopped or moving slowly was really difficult. So I went back to bias ply. The tires on my truck are old so I am replacing them, though.

Wheel ballance or bad tires , as Denny says. Alignment usually does not cause vibration. Also since you keep saying you are sure it happened after ujoint replacement that you yourself did, you may have got something messed up, needles: missing, crooked, smashed and/or cups not on right, wrong ones, bad out of the box, etc. Check the lug nuts as mentioned AND THE WHEEL BEARINGS AND THE CASTLE NUT AND THE COTTER PIN!!!!!! If you have any other tire/wheel combos or can borrow some, try them on the front, that will tell you alot.

I had new tires put on today and balanced them, obviously. The front end was out of alignment. So I will see how it rides after that and then go from there. Thanks for the insight.

I had a U'joint binding in an old van. It sure did a lot of jumping and hopping, especially when I let off the gas. It was almost like a bad shock. I can't say I felt it in the steering though. Anything is possible though. These old trucks have bronze spring bushings instead of rubber, and the steering shaft is in a solid tube from the wheel to gear box. You cold be feeling it in the wheel.