Cv joints

I own a '98 Plymouth Voyager, with 155,000 miles.

I have a vibration I think in the front end which starts at about 52 mph, peaks at 55mph, then dwindles down a little by 60mph, but never really goes away beyond that. It afeels like worn shocks. But as far as I can tell the shocks are ok. Hitting a bump does not initiate the problem. Only speed.

Last year I was told I had bad tires, Goodyears, they have flat spots on all four of them. So I went for the big $ and bought new Michlens. Had them rebalanced 3x so far, and the problem does not go away.

My meachanic suggested cv joints may be bad. The boots look fine, and no noises are being made. Last fall I took the tires and brakes off the car blocked up the front end, Put the trans in gear. Same result, vibration starts at 52 mph. AAMCo man(friend) said I could not tell by doing that.

Any suggestions? I Feel the car is worth repairing.

You might have a bent or out of balance long shaft,(RHS).
Check the inner CV joints for play.
And had it been on Acceleration I might have suggested checking engine mounts as well.
I don’t know is the crank end pully includes a damper, Does it vibrate only when the shafts are rotating or with engine rpm.

You might try your idea again with one wheel chocked, then the other and see if there is a difference between sides.

Also move the wheel front to back, JIC you have a buckeled wheel.

and you could also check with the brake disks removed see how it goes.
If spinning the wheels with one wheel chocked, remember 30 on the clock is 60 at the wheel end.

First off, if you haven’t replaced the struts on your van, you’re way past due. In addition to a lousy ride, bad struts result in flat spots on tires. That happens because the struts can’t keep the tires on the road, They bounce and as they do that, they wear rubber away. Read this great article on the importance of struts.

http://free-auto-repair-advice.blogspot.com/search/label/struts

As for the CV joint…it could cause a vibration. But you’re wasting your time replacing a CV joint if you plan on leaving the worn struts in place.

I’m a retired ASE Master/L-1 Technician. I still keep current with the latest automotive technology. Visit my blog for cool articles and TSB’s: http://free-auto-repair-advice.blogspot.com

I have been told that a worn inner CV joint could cause vibration, but so could bad struts, or a alignment problem.

The problem started in the first sentence “I own a '98 Plymouth Voyager” When I saw they were offering the lifetime warranty on drivetrain systems sold on the new cars my immediate thought was “Well, they will be out of business in a few years.” I never went to school to be a mechanic yet that is my profession and the business that I own. I owe all my experence and gratitude to Dodge, my first car, I never had enough money to get it fixed and was forced to do it myself, just about every other day. I’ve owned five chrysler products all with very bad results. I have found the most important tool to own pertaining to Chrysler cars and trucks, a cell phone to call some one to pick you up. Sorry for the rant, back to the question. With that amount of miles a lot is possible. The torque converter could have a build up inside of it causing it to be out of balance, worn inner cv joints will cause a vibration but usually under accelleration once at a maintained speed the vibration will decrease or go away. Worn outer cv joints will cause a vibration in worn to the extent that it is out of balance. Same thing goes with wheel bearings and the even the transaxle differental. In most cased a bad wheel bearing woul dbe heard as a groaning rumbling sound and increases and decreases as weight is shifted while turning left or right. Samething goes for outer cv joints you nomally hear clicking sound in sharp turns as in parking lot manuvers, or as you firmly hold the brake putting the van in gear from reverse to drive you amy hear a sound like knuckles cracking. As stated before by another post a slightly bent half shaft could also cause vibration. I’d presume the van is not an AWD? Some tests you can try is jack up the right side of the van keep the tire on and put it in to gear, (turn off the traction control if you have it) accellerate slowly to about 25-40 mph do you feel the vibration? do the same test to the opposite side do you feel the vibration? If the vibration is felt on both tests the problem is more then likely internal to the transmission. If felt only on one side inspect the wheel bearing if the bearing is good replace the axle. It may be necessary to compress the suspension a little bit by placing a block or another object under the control arm so the axle isn’t stressed by the suspension being fully extended. One more test run the van in neutral at about 1800-2500rpms is the vibration felt? if so it in in the engine, torque converter or possibly the transmission oil pump or main shaft.