Been there! Have had to go as far as deflating tire, bust bead lose, rotate tire on rim 90' at a time, rebalance, try it. Really only applies if you have a rim/tire using a lot of weight to get balanced. Going to a shop using the road force capable machines could make a difference also.

Well, front axles are fully seated.

I had the tires rebalanced this morning with a road force balancer, with no change in vibration. The tech said they were already pretty much good to go.

Taking the wheel spacers off the front made no difference in vibrations.

I dropped the tire pressure from 40psi (really tire shop?) to 30psi and drove around for a few minutes and the vibration seems a little bit less harsh and it seems to start at a slightly lower speed, but that's completely subjective.

I'm leaning towards the wheels and tires being out of whack, but I'm going to go pull the rear driveshaft and see if there's any play in the DC joint with it out of the truck.

Looks like you have a direction to go I'd say.
Point A: Rim surface to spacer, spacer to disc.
Point B: CV axle shaft locked.
Ends of the spectum, between those two points are two true surfaces both sides, that rust can interfere with.
Rotor to Hub: Could fit cause problems?
Kentuc snow/rust belt??
What condition were surfaces in?
Did you remove rotors during job? Rust?
Mine required deep clean wire brush on die grinder, hub a mess. Don't live in rust belt far from it.

There was some slight surface rust, but no buildup by any means. Certainly less than my Sierra. This 4Runner came from Charleston, SC in April so it's not been exposed to road salt ...yet :/

Once again I'm starting to lean towards the driveshaft being the culprit. I pulled the driveshaft earlier and while there wasn't any slop in the double cardan joint, it wasn't tight at all and was bone dry. I must have missed the grease zerk when I greased the driveshaft last time. I read that if you can see the bearing surface in the cardan ball, the joint is shot - and I can see it plain as day.

Greasing the driveshaft and the DC joint in particular seemed to soften the vibration for a few highway miles but it's back again and I've noticed it's there very subtly at around 45mph and it comes and goes based on throttle.

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By the way, I want to say that I appreciate everyone's input. It's all been super helpful.

This came the other day. I'd tell y'all how it affected the vibrations but it turns out the transfer case output flange bolt pattern is 6mm different than the rear axle flange, which was kinda hard to tell upside down in the dark with a standard tape measure.

The good news is that Tom Woods was willing to refund the cost of this shaft as long as I pay to ship it back and is making me a new one. They've been awesome to deal with.

For posterity, the measurements I took (the right ones) are 45-3/8" flange-to-flange at ride height, with the 60x60mm flange at the rear axle and 66x66mm flange at the transfer case, pilot on both ends is 1.812". This is for a 2001 4wd with auto trans, multimode transfer case, and non-elocker axle with 3" lift.

Measure once, cut twice, kids.

Well, after installing the new driveshaft and driving it a couple of days, the vibrations are still there. Maybe not as bad, but definitely still there. This weekend I'm going to swap the tires front to rear and see if it changes the vibrations any.

If it's not wheels and tires, the only other thing I can think it would be is just that the pinion angle isn't close enough to parallel with the driveshaft angle and even with the new driveshaft it's vibrating. If rotating the tires doesn't make any difference, would driving at 65mph for a couple miles in 4wd with no rear driveshaft cause damage?

Anyone have any other ideas?

Woody is awesome about his customer service and his drive shafts are top notch! The folks over on the XJ forum swear by him.

Yeah they really took care of me and my inability to read a tape measure. I'd absolutely do business with them again.

I realize I've been posting in this thread like crazy, but this is driving me crazy.

This afternoon I measured the angles between the rear axle and the driveshaft and it's about 5° difference. I used an angle finder from work in the parking lot, so I couldn't drop the driveshaft to get a solid measurement from the pinion flange so I used the axle housing itself, but it appears to be perpendicular to the pinion shaft. If anyone knows otherwise, please let me know.
Axle housing (perpendicular to the pinion shaft?) was at 5° from vertical, and driveshaft was at 10° from horizontal.

This seems like it could cause the vibration I'm feeling, right?

Now I think it's in the front end. I put it in AWD and went for a drive and noticed that the vibrations are MUCH worse, they start at about 50mph, and they drop off noticeably when I'm coasting.

I talked to Toytec earlier and they suggested removing the diff drop and seeing if that changes the vibration, which might help isolate a bad CV as opposed to a bad bearing in the diff.

The front driveshaft shouldn't spin much in 2wd, right?

I had a bad vibration like yours caused by my tires being out of balance. When you bring it to a shop see if they will let you watch them balance. Some people don't check the run-off which and throw it off by .25 ounces which made mine shake


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I had very similar symptoms after installing my lift. After an alignment, there were no vibrations.

I am at my wit's end with this ****in thing.

New CV axles did not make a difference.

I'm going to have the tires rotated and balanced AGAIN on Monday.

It's been aligned, tires have been road force balanced twice this month, new Tom Woods driveshaft, new CV axles, I've tried driving with and without the wheel spacers.

Any other ideas?

Post up your alignment printout. They should have given you one.