Bad vibrations (Part 2!)

[Dave145]

I'm avoiding the rear end because I don't have free money or a whole bunch of time to tear into the stupid thing to look at it. Would need a gasket and fluid change at the very least, and there's not a single person here that would open up something like that and not feel compelled to overhaul it "just because".

Again. I'm not wasting money on stuff that isn't broke. I'll spend the money on whatever parts turn out to be bad, but throwing money away hoping to solve this issue is downright stupid.

 

[Glenwood]

Checking every major component is not a waste of money with a serious problem like you have. Hopefully that differential doesn't lock up on you while on the highway.
For cost of a gasket and lube, it might be worth pulling it out and do an inspection. Post some pics of it here . There's lot's of experts here that can provide some guidance ( @Cranky 747mopar and 5.7 hemi) to name a few. You may find a good used pumpkin locally to swap it with?

 

[Fran Blacker]

You changed axle bearings, did you check axle side play afterward? I'm not familiar with keyed axle side play settings. If there is to much side play it may explain right wheel vibration at speed. Changing bearings could change the amount/thickness of shims to get side play right.

 

[KENTON]

I know you said you have tried a couple of sets of tires already, but I think from all the checking you have done you need to get a full set from a friend that are known to be smooth as silk up to 80 or 90. You might have a bad one or two (belt seperation or something.)I chased my tail on a vibration that sounds very much like yours. I got tired of the wheels and tires that were on it and when I changed my vibration got 80% better. I am going to find a known smooth set and see if I can get the other 20%.

 

[Dave145]

My friend said it definitely felt like a bum tire. I will check with him to see if he's got a set I can borrow.

When I did the rear axle bearings I did not check the side play of them. That sounds like something very much worth checking though!

I also wonder if there's a way to get may brake drums balanced as well to rule that out...

 

[5.7 hemi]

Swap tires front to back and see if there’s a difference.

 

[Brewzer67]

Checking every major component is not a waste of money with a serious problem like you have. Hopefully that differential doesn't lock up on you while on the highway.
For cost of a gasket and lube, it might be worth pulling it out and do an inspection. Post some pics of it here . There's lot's of experts here that can provide some guidance ( @Cranky 747mopar and 5.7 hemi) to name a few. You may find a good used pumpkin locally to swap it with?

I couldn't agree with this more. Nothing on a car likes extreme vibration. The longer it stays that way the more likely something is going to break catastrophically. Two quarts of gear lube and a gasket are only $22 at Napa. If cash is truly that tight (and I get that it can be), PM me your PayPal info and I'll send you the cash. I would hate to see you lose your ride (or life) for $22.

 

[Dave145]

This week I will get the tires roadforce balanced and confirm with the driveshaft shop what speed they balanced the driveshaft at when they made it.

If the rims/tires and driveshaft come back good, I will look more into the drum balance, wheel bearings (I don't think they're bad again, but worth another look), and rear end guts.

 

[the mississippi madman]

Don't forget to check the trueness of your axle flang when you finaly dig into the rear

 

[Fran Blacker]

This week I will get the tires roadforce balanced and confirm with the driveshaft shop what speed they balanced the driveshaft at when they made it.

If the rims/tires and driveshaft come back good, I will look more into the drum balance, wheel bearings (I don't think they're bad again, but worth another look), and rear end guts.

Axle end play while your there changing tires. Since the reminders are being added.
Did you look at mymopar for that 64 Chrysler service manual? It's good for drivetrain stuff useless for body/interior help.

 

[Dave145]

I have not looked for the manual, as I haven't had the time to. I'm not sure what the spec should be for end play, but I know that the axle doesn't move back and forth. I tried shaking both shafts and tried pulling on them a bit to see if they had excessive movement when I rebuilt the rear brakes and they seemed okay to me.

 

[Dave145]

I still don't believe it's an axle problem though, just like the pinion angle thing. I've had multiple people more experienced than I drive and look at this car, and every single one says the same thing. An axle isn't going to set off the vibration. If it was the culprit, the vibration would be a higher frequency and shorter wave kind of vibration, similar to a bad u joint. This is definitely not that kind of vibration. This vibration is felt in the floor, but is extremely coarse. It feels more like the car is coming apart or has a tire about ready to explode.

Hence why the axle is on the back burner for now.

 

[MNBiker]

The brake wouldn't be adjusted a little to tight on that side. Just throwing my 2 cents in.

 

[Dave145]

No the brakes are adjusted fine.

 

[oldbee]

I have forgotten all the beginning stuff,lol. I just can’t believe anything inside the rear axle is going to cause the vibration & still be driveable. Usually, diff problems are howls,whines,grinding. I still think something else is going on, driveshaft, pinion angle,etc. 99% of the time for vibration in the floor, it’s something from tailshaft on backward. Frt end is in felt in steering whl.

 

[Dave145]

Well currently I've tried and replaced everything back there, so the chance of really anything else being bad back there is virtually zero.

With the car in park I can run the motor up to around 1500 RPMs and feel a pulsating vibration go from the front of the car to the back. Around 2000 RPMs this pulsation goes away and smoothes out a bit. By 2500rpms sitting still I feel a vibration similar to the one I have when I'm on the road. It's a moderate pounding kind of vibration, coming from the front floor and working it's way backwards.

 

[dryheat]

If you are getting a noticeable vibration in park then I would look at the torque converter to make sure that if it had a weight that the weight is still there ... make sure it's still bolted to the flexplate properly ... is it an internally or externally balanced motor?

 

[Dave145]

I have had the inspection cover off the trans and I rotated the torque converter by hand to check for weights. I do not see any areas on it that look like any weights have fallen off. The flexplate appears to be okay as well. I stuck a thin mirror up there and a light to check it out and I don't see any cracks.

I believe the motor is extrnally balanced.

 

[dryheat]

I'm sure someone smarter than me will chime in ... but I believe that on an externally balanced cast crank you will need a weight on the torque converter. Is this a push button in your 64 or did you convert it to something else?

 

[747mopar]

Well currently I've tried and replaced everything back there, so the chance of really anything else being bad back there is virtually zero.

With the car in park I can run the motor up to around 1500 RPMs and feel a pulsating vibration go from the front of the car to the back. Around 2000 RPMs this pulsation goes away and smoothes out a bit. By 2500rpms sitting still I feel a vibration similar to the one I have when I'm on the road. It's a moderate pounding kind of vibration, coming from the front floor and working it's way backwards.

It makes it really hard for us to help diagnose with the symptoms changing. I thought in the beginning it was only while driving and within a certain rpm which narrowed it down, now that your saying it's even in park we're back to the motor and torque converter? A bad plug, wire or distributor cap causing a miss, broken torque converter bolt, broken flexplate, motor or trans touching the body or possibly an internal failure could all be a culprit if it vibrates in park.

So did it not vibrate in park originally? If not I'd backtrack things you've done since to see if you moved something causing contact with the body.

You must have posted your last response while I was typing.... converter and flexplate are good.