Vibration after lift

[yellow dog 62]

After installing OME 3" lift my '88 FJ62 has developed a vibration that occurs at approx. 55mph and gets steadily worse to the point of shaking the dash and doors. We discovered the bearing for the output shaft to be bad, so we replaced them as well as the input bearings. We had the drive shaft balanced and timed. The vibration has not changed after doing these things. The angle on the drive shaft is 10 degrees. Is that the corect angle? What else should I check? Thanks

 

[82-SOA-60]

Did you make sure you put it back in the correct synch?

 

[gulp3000]

Dang, no idea. I can tell you that I developed a wobble after putting on 33's and I changed the tie rod ends and stabilizer. Did you use longer shackles without using caster correction wedges? Not sure if that could cause it.

 

[hodag]

What does your pinion angle look like? Thats the first thing I'd check. Also make sure the driveshaft isn't out of phase.

Hodag

 

[82-SOA-60]

What does your pinion angle look like? Thats the first thing I'd check. Also make sure the driveshaft isn't out of phase.

Hodag

That's the phrase I was looking for. In phase.

 

[Aseif007]

If the shafts are in phase and the driveline angles are OK and your tires are balanced, and your hub and axle bearings are good then I would look at the output gear in your t-case. How many miles do you have? I had around 210,000 when I installed the same lift and I eventually developed the vibration. I could not track it down. After I put on the BFG mudders it was still there, but not as bad as the tire whine so I just got used to it. Well when I went to rebuild the t-case I didn't look at the output gear, and after the rebuild the vibration was still there even after I installed the motor tranny and t-case in a different stock geared and height FJ-62. Well later I was removing the t-case to sell it and I looked at the gear that is on the output shaft of the A440F and the splines on the output shaft were sharp and so were the splines in the gear. That would allow the gear to move without the shaft moving while it was on the splines. Well I thought that this was due to my high milage 290,000.


Fast forward to yesterday, I was taking apart the t-case of our donor 89' FJ-62 with 160,000 miles on it and it had the same sharp splines on the shaft and gear. That is too low of a milage for this to happen IMHO. The only way to check this is to disassemble the t-case and inspect which is not that easy if the driveline is on the car. Just another thing that it could be, this is common for the FJ-62; that's why the McNamera gear is so sought after. Good luck on your quest to solve the vibration.

 

[dogboy2]

U-joints....if they are still original as in original to your previous suspension setup. They have a wear pattern to your old driveline geometry and now that the angles of your drivelines have changed, the old joints are protesting a bit. I would suspect this especially if the vibration only occured post-lift and given that you've balanced the driveshafts and already replaced the rear output bearing.

Try:
1) replacing the u-joints with new OEM
2) verify that the shaft is in phase - one trick: you can pull the driveshaft and rotate it 180˚ on the companion flange, retorque, and see if that calms things down - the driveshafts and flanges are factory balanced together at the time of assembly. That's why it is important to put match marks on both the companion flange and the driveshaft flange before disassembly so that it goes back together in a balanced condition.
3) check pinion bearing on rear pumpkin
4) have driveline shop verify and/or straighten your driveshafts

OME suspensions have built-in castor correction so your pinion angle should be O.K. without needing to run castor correction shims.

HTH, BTDT,
-dogboy- '87 FJ60

 

[Mark W]

U-joints....if they are still original as in original to your previous suspension setup. They have a wear pattern to your old driveline geometry and now that the angles of your drivelines have changed, the old joints are protesting a bit. I would suspect this especially if the vibration only occured post-lift and given that you've balanced the driveshafts and already replaced the rear output bearing.


OME suspensions have built-in castor correction so your pinion angle should be O.K. without needing to run castor correction shims.

HTH, BTDT,
-dogboy- '87 FJ60

Ujoints don't wear into any sort of pattern. If they do, then they are flat out worn out.

OME suspension on '60s often need shims to acheive the correct caster and pinion angle.


Mark...

 

[dogboy2]

Well Mark,
Not to argue with you, but my experience with my OME suspension lift and drivelines was just that: severe vibration after lift, new output bearing on the t-case, new companion flange, with the problem solved by straightening and balancing both driveshafts but only AFTER I replaced the u-joints. Replacing the u-joints was the last thing I did after all of the above failed to rectify the problem. Like Yellowdog, the vibration did not exist prior to the lift. New u-joints, in my case, was the right solution and ultimately eliminated the vibration.

Again, every setup has its quirks, but having installed castor correction shims with my OME suspension, the truck handled very poorly and after several conversations with 3 different ARB tech reps, I removed them and handling performance was restored. ARB's official stance on this issue is that castor correction is built into the spring system and no additional correction devices are required. This was certainly true with my setup, but each situation requires its own solutions.

I write from my own direct experience, as do you, both of us with the intent to help.

No disrespect intended,
-dogboy- '87 FJ60

 

[Tapage]

did you have a pics of your drive shaft . ?

 

[notatreehugger]

Change u-joints...Same thing on mine. 40-50mph vibration...new u-joints she is pretty smooth...do the cheap stuff first.

 

[Mark W]

Well Mark,
Not to argue with you, but my experience with my OME suspension lift and drivelines was just that: severe vibration after lift, new output bearing on the t-case, new companion flange, with the problem solved by straightening and balancing both driveshafts but only AFTER I replaced the u-joints. Replacing the u-joints was the last thing I did after all of the above failed to rectify the problem. Like Yellowdog, the vibration did not exist prior to the lift. New u-joints, in my case, was the right solution and ultimately eliminated the vibration.

Again, every setup has its quirks, but having installed castor correction shims with my OME suspension, the truck handled very poorly and after several conversations with 3 different ARB tech reps, I removed them and handling performance was restored. ARB's official stance on this issue is that castor correction is built into the spring system and no additional correction devices are required. This was certainly true with my setup, but each situation requires its own solutions.

I write from my own direct experience, as do you, both of us with the intent to help.

No disrespect intended,
-dogboy- '87 FJ60

None interpeted.

I submit that your ujoints were simply worn and a little bit lose. A steeper angle will accentuate any slack in the system. It is not uncommon for a lift to bring out flaws like this. But it's not because the joints have developed a "sweet spot" or anything like that.

As to the caster shims... I've had three different rigs measured on an alignment machine while chasing squirrelly handling after OME installs. All were OME heavies and all fell into the 0 to -2 degrees of caster range. Shims made them right.

The OME rep can claim what they want, but... Ah wuz der and Ah seen it.


Mark...