Front driveshaft causing vibration, not the driveshaft itself
I have been trying to get to the bottom of this problem for a month now, and sadly have made little progress. Any advice would be greatly appreciated.
Back story: Clicking developed when turning and braking. Naturally I replaced both front cv axles. Didn't change anything. Next I took out the front driveshaft. Drove around the block, no clicking at all. Grabbed an exact driveshaft from a U-Pull It yard. Shaft was the same length as the one I had. Put it in.
Current Problem: Vehicle vibrates at speeds above 60mph (not as bad as a death wobble, but enough). Vibrations started about 300 miles ago, I've been easy on it since. May be coincidence, but after a 70mile trip at 59mph (and once or twice hitting vibrations speeds), came to a stop to find a terrible burning differential smell, with fluid leaking out both sides of the front axle and a bunch of "whining" noise. I was able to "tip toe" it home. Took the driveshaft to driveshaft shop. Guys looked at it and said its not the problem, the driveshaft is perfectly fine. On the way home, left the driveshaft out, and found the vibration is non existent at 60.
Short: Replaced driveshaft with a used U-Pull it. Vehicle vibrates above 60, has leaked some differential fluid out sides of axle. Took driveshaft out, vibration is gone. Took the driveshaft to driveline shop, and they looked at it and said its more than fine.
you need to rebuild your front diff, pop the cover off and check the fluid, then lift both front wheels with the front driveshaft out and turn your wheels to inspect the gears and listen for any crunching etc. if all seems well there grab some gear marking compound (prob pick some up at any parts store. you could use bearing grease if your real desperate) and check your gear pattern, you will be able to find the proper meshing pattern online.
Also if your have a quadratrac transfercase make sure your tires match on all 4 corners and not 2 new and 2 old (if they are different the diffs will spin at different speeds and cause all kinds of issues)
Definately something in the front diff, bearings etc.
And just a side note, be carefull when you have the front drive-shaft out on a zj with a 249, before model year 1996, they have been known to roll, even when in park.
Do you still have your original drive shaft? If so, swap them back out.
I just went through something similar and it turns out the centering ball in the double U-joint was about 1/8" worn down. This caused me to have vibrations start at 40mph and steadily get worse as speed went up. Never made it to 60mph with it like that, didn't want to grenade the shaft completely at that speed.
Sadly I no longer have the other shaft. I turned it in for the core. That's not too upsetting considering the original one was big time shot, the loudest clicking clacking you'd ever hear. But now all I did was inherit the vibration problems.
I'm not driving the jeep since I know itll wear out the 249 in a heart beat.
Another thought, is it possible that the driveshaft is fine and somehow the problem lies solely on the differential? Although the vibration non existent with the original driveshaft OR now with the front shaft removed...
Well today I'm going to take it by a shop specializing in jeeps and have them do a diagnosis and quote it. I still haven't been able to get to the bottom of it. This way hopefully it can just be dealt with, so long it's not too pricey. I'll write back with what the outcome is. Thanks for the help.
I have the same issue. Now my ZJ has 270,000 miles and the VC is burned out. Drives fine with the front driveshaft out. But when I put one in it has a pretty good vibration. Havent had a chance to look into it yet.
1996 ZJ Green Laredo V8, 2.5" OME and Bilsteins, 33's, Holes drilled in the roof.
1998 ZJ Platinum Limited 5.9, Backyard parts fodder
1987 Mercedes 300D Turbo, the diesel daily, 30mpg in style
Originally Posted by Texas ZJ1
I heard someone yell "mall crawler" from the back porch. I'll go see who said that. Be right back.