zegnaguy

iTrader: (1)

What is the problem and what needs to be replaced?

Rear end scary sloppy on my 93 sc300 NA -6spd. (Miles 245K) Noticable everytime you hit the gas semi hard. Rear of car immediately feels like it sloshes to the left then back right, side to side the rear wheel must still be going straight. Only evens out when you let off the gas. Happens at low speeds and highs even scarier.


History Suspension and Drivetrain work:
-All 18 oem suspension bushings replaced with Diazen poly bushings. Front, back, lower, upper, sways.
-Tein flex Coilover.
-Diff (4.27 auto no LSD) drained 300 miles ago before problem. replaced with oem recommended 80-90diff fluid. no gray liquid or shavings.
-Single solid drive shaft from 6spd to custom diff adapter.
-Looked underneath last night nothing seems to be loose.

When first installed 6spd this problem didn't occur it progressively started happening until really bad right now.


What is the problem and what needs to be replaced? What are the signs of axels/joints going out? Could it be the diff pumkin bushings wore out front or rear. wouldn't think they would cause this much flex more wheel hop if anything.

what kind of tests can I run to find out the problem?

Na-t comming next month so need to solve this before even more power than stock.



Everybodies Input is appreciated!!

GSteg

iTrader: (15)

This seems to be a problem for lexus. The way they connect the rear suspension frame to the chassis frame is through rubber bushings, at least on the GS. The rear end wiggles when you exit out of a turn and such.

We tackle this problem by using lower rear chassis brace of the Tom's 6 link. They are metal braces that makes the connection from the suspension frame to the chassis frame more rigid.

zegnaguy

iTrader: (1)

So your thinking that its the subframe flexing to much on the rubber bushings connected to the frame?

Are you thinking that if I put solid aluminum subframe mounts in there that would cure it. I haven't really noticed it in and out of turns more so in straight line and pushing on gas half way.

GSteg

iTrader: (15)

I do not know enough about the SC to make comments on what should be replaced. All I know is that the GS guys experiences rear end sloppyness through turning or sometimes even hard acceleration. Perhaps you can try taking turns to see if the rear end jiggles a bit when you exit?

zegnaguy

iTrader: (1)

How much jiggling are we talking. For me its so much I don't want to power thru it as it feels like your looking control but your still going straight. Its enought that I wouldn't want to do it at high speeds. If you gradually put on the gas it isn't very noticable. push the gas half down or all the way and you feel like your fish talking with out the tires leaving a straight line.

Very very fustrating. I can't afford to put the other turbo'd motor in and not have this fixed otherwise I'll be in the ditch for sure when breaking the tires loose and having a wobbling rear end.

shlounek

iTrader: (1)

I have the same problem, Its even scarier when it is RAINING,

and I already lost control twice, so prolly my condition is the worst.

same thing no accel under straightlines or high speed, i feel the whole rear end is rising on ice.

1badsoarer

I had the same problem in my soarer until I changed suspension and tires. Most cars that have the problem either have A.) A blow strut or jacked up spring, B.) Tires have little to no tread on inner side or C.) Subframe bushings. I didnt change my subframe bushings, just Tein coilovers and new tires.

zegnaguy

iTrader: (1)

Problem solved, I retorqued all the rear end bushings and found that the poly bushings had settled a little. Also the rear lower control arm camber adjustment side was torqued way to low from the alignment guy. Drives the way it should again. Thanks everyone!

zegnaguy

iTrader: (1)

After just going thru this I would highly recommend retorqueing to spec all the rear bushings etc. then take for test drive.

shlounek

iTrader: (1)

thanks it sounds like an idea i will try it out and see if there is change

2JZ_SC

Off the wall thought, Look at the rear wheel bearings. If there is sloop in them when you give it gas and the bearings are not true, there will be a funny “hop” in the rear. Just a thought (you do have 245k on it, mine died at 100k)

shlounek

iTrader: (1)

What do you mean by slop, Recently I noticed something, if my car is in my garage for a couple of days and i dont use it.

The instant i take off the handbrake and release the clutch i feel like one the wheels is being held, and then i get a loud pop and the wheel is free again, its basically the wheel is being.

I already replaced one of my wheel bearings but that was basically after I hit a really bad pothole here in michigan a while back.

Dougspeed

iTrader: (2)

That's normal if you haven't driven the car and moisture has collected on the discs. The parking brakes rust and get stuck to the drum until you release the brakes and the car starts rolling.