Vibration after installing new poly bushing on the rear end.

[evanstewy]

I just replaced the bushings on the upper, lower control arm, stabilizer bar and tension rod only on the rear end. Now there is a vibration that vibrates the whole car when I accelerate. It's not that bad when I accelerate but it's really bad when I am in 2nd or 3rd gear at about 4000rpm and I let off the gas. Also note that it does not vibrate when I'm in neutral and rev. The only thing that I can think of is something wrong with the drive shaft.

One last thing is before I changed the bushing I was getting a rattle from the lower control arm because it felt like the bushing was loose inside the control arm. So that rattle might have been covering up the vibration that I'm getting now with the new poly bushings.

I also took some photos on how to remove the bushings with a ball joint service kit from Harbor Freight if anyone wants a DIY. Let me know if you want me to write up a DIY for that.

[KonaTrueno723]

Was this an existing prob before replacement or right after the bushings got put in?

Yeah, i'd post this in the DIY section.. It'll do good for others & help counter problems your experiencing now.

Edit: Duh.. Already mentioned in the titled post.. Umm u-joints? Had the same problem after installing my DIY rear links. Found a bad u joint & now my car is no longer drivable..also check for driveshaft wobble, center DS support bearing ect..

[evanstewy]

Thanks. I will check the u-joints and the support bearing.

[gaijin_rokurunner]

probably changed the pinion angle some and threw off the correct degree of the drive shaft angle...old warn joint or center bearings.....or could be a tranny mount issue they sometimes split and u cant see it but feel it...if no vibration when u rev or are in neutral could be a tranny issue...if your in neutral and driving at a specific speed the drive shaft still spins and should also vibrate...

[KonaTrueno723]

gaijin_rokurunner..to your knowledge, has anyone you know ever attempted to repair or replace the ujoints on these factory 2 piece DS? I already went to every parts store & of coarse, no listing or replacement ujoints in their database. Not even on line.. For a 25 yr old car, I'm surprised anyone elses DS's hasn't fallen apart yet..anyone but mines go figure! But then again it is a Toyota, & it keeps runnin & lasts

[gaijin_rokurunner]

no not that i know of and they are not rebuildable thats why i sell carbon fiber one piece shafts with rebuildable joints....eliminates the center bearing, absorbs vibration and reduces the weight by half....

[KonaTrueno723]

no not that i know of and they are not rebuildable thats why i sell carbon fiber one piece shafts with rebuildable joints....eliminates the center bearing, absorbs vibration and reduces the weight by half....

10-4 gaijin.. & that's why im saving up for one. I'll let you know cause i've heard your carbon fiber ones are bad ass

[gaijin_rokurunner]

well they do provide a crap load more performance then a 800 pair of battle version control arms or a set of bash bars which all cost around the same or the other one piece drive shafts sold for ae86s...ive been selling them since 2005 and not one complaint...all satisfied customers...i had a better write up on the old club4ag with more pictures but thats gone so had to start fresh...i would do a group buy again but last time 5 people backed out after i ordered and paid for the shafts and i got stuck with 3500 worth of drive shafts ....i eventually sold them all but wasnt an ideal situation for me as im not a shop with constant income flow or credit ...im a working man lol anyhow if you have any questions feel free to email me anytime

[gotzoom?]

The PR section of the service manual has the test procedure to determine if your driveshaft is bad. I'd check it before just buying a new one. If the u-joint is out of spec, the service manual says to replace the driveshaft.

[evanstewy]

Thanks for all of the suggestions. I have not been able to get under the car yet to try anything yet. That is a good idea to put the car in neutral when it is vibrating on the road. I will keep you guys posted on my progress.

gotzoom: So I'm guessing by what you said that the 87 GTS has the shell type? Not sure what the difference is between that and the cord coupling type.

gaijin_rokurunner: If it did change the pinion angle then how would I correct that without adjustable 4 link setup?

[KonaTrueno723]

evanstewy=the bushing replacement should've put everything back to original specs and pinion angle..that's at a stock height & level tho'..If its lowered, that's a different story

[KonaTrueno723]

The PR section of the service manual has the test procedure to determine if your driveshaft is bad. I'd check it before just buying a new one. If the u-joint is out of spec, the service manual says to replace the driveshaft.

Yeah i did see that in my SM too..dangit!

[gaijin_rokurunner]

only way to adjust pinion angle without adjustable 4 links is to shim your tranny mount or cross member....but u can only adjust it a degree or 2 that way

[evanstewy]

I was able to test hitting the clutch while it was vibrating yesterday. At about 3500rpm I would let off the gas and it would start to vibrate and it would stop vibrating the second I hit the clutch. So it does not look like it is the drive shaft after all. I will be checking the transmission mount today.

Also could this just be a vibration that was already there but I'm just noticing it now because it can transfer to the chassis with the new bushings? Should I be that worried to find out what it is?

[BoRoYaSui]

I have noticed this same issue on two of my ae86 where installed prothane bushings in the rear. it annoying but i never had any issues. I believe it is because of the harmonics of the rear suspension because it happens during a certain rpm band and under load. The factory rubber bushings are much better at dampening which is probably why you didnt feel it before. I have considered switching back to rubber but I have learned to live with it.