Bad Vibrations between 35-45 MPH

[JeepcoMJ]

 

Draggin' this up again to report the vibes are finally GONE!!! In the very first post when I started this thread, I said the vibes started when we regeared, but like a dumbass I had to try EVERYTHING before I went back in the diff like I should have done originally - you were right roger21maynard. Most everyone said the diff couldn't/shouldn't cause low speed driveline vibes like I had, but it dayem sure did. The problem was pinion backlash - there was none. On the original install we could not get the crush sleeve to crush, so we re-used the original and tightened the crap out of the pinion. This week we looked at the pattern, and although there was very little metal in the diff, you could see where the pinion and ring gears had tiny dents in it caused by chattering 'cause it was too close to the ring gear, which caused the vibes. At first I only had vibes under acceleration, then it progressed to deceleration, then to coast during the 35-55 MPH speed range. And the strange thing is that the diff was very quiet during the whole time - made NO noise. This was a strange one and I thought I'd pass it on. Expensive hard-learned lesson :mad:

 

But anyhow, I learned a lot about driveline angles, slip yokes, u-joints, drive shafts, alignment, and DIFFERENTIALS. Everything's right now, and I'm happy. :cheers:

 

.....

 

If this is a vibration with no handling issues to go along with it you can eliminate any steering, ball joint, suspension problems.

 

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You did change gears and that would have been my first guess except you said the problem was there before you changed gears and is now just more pronounced. So I don't think your gear change is the culprit but you are getting close because what you did had an effect on the vibration.

 

opsled

 

cost;

Time,

Money,

Lesson learned....(check and double check everything. always start with what made the change for better or worse...and you come to your culprit)

[HOrnbrod]

Aye, opsled too. :nuts: on my part. What led me astray is that most everyone else said that the diff could not cause low speed vibes. Lesson learned, point taken, and this old dog has learned a new trick. :oops: So overall it was a good, although expensive, experience.

[MiNi Beast]

Good to hear it all worked out. Sorry you had to go through all that but what a learning experience. Well if I have any drive line questions I'll be sure to ask you.

 

 

 

 

I can tell you right now it won't be the tranny mount. But check this before throwing more parts at this. Rule of thumb is if figure out problem area then first check area of last area you fixed. Get it? A gimme that things where out, but doing a major job like this and that be the area the problem arises in whold have been the first place to check. I didn't check mine being never messed with gears but you have so. But hope it isn't the problem due to time and money if it is the problem but would check there.

 

Yes, I know that's the first thing you do when troubleshooting; go back to when the problem first started. But I did have these same vibes before the gear install, although very faint. The gear install made the vibes worse, but did not change their freq or the 35-45 MPH range where they showed up. And they are very quiet during accel, coast, and when braking. Course I know that sometimes doesn't mean squat either. :mad:

 

Draggin' this up again to report the vibes are finally GONE!!! In the very first post when I started this thread, I said the vibes started when we regeared, but like a dumbass I had to try EVERYTHING before I went back in the diff like I should have done originally - you were right roger21maynard. Most everyone said the diff couldn't/shouldn't cause low speed driveline vibes like I had, but it dayem sure did. The problem was pinion backlash - there was none. On the original install we could not get the crush sleeve to crush, so we re-used the original and tightened the crap out of the pinion. This week we looked at the pattern, and although there was very little metal in the diff, you could see where the pinion and ring gears had tiny dents in it caused by chattering 'cause it was too close to the ring gear, which caused the vibes. At first I only had vibes under acceleration, then it progressed to deceleration, then to coast during the 35-55 MPH speed range. And the strange thing is that the diff was very quiet during the whole time - made NO noise. This was a strange one and I thought I'd pass it on. Expensive hard-learned lesson :mad:

 

But anyhow, I learned a lot about driveline angles, slip yokes, u-joints, drive shafts, alignment, and DIFFERENTIALS. Everything's right now, and I'm happy. :cheers: