JimsGX

Hi,

Does the 1st Gen have a replaceable tranny filter? Do 1st Gen transmissions suffer from any shudder problems? Does a drain and fill take about 2 quarts?

I'm taking a closer look at my tranny in trying to find the root cause of my driveline vibration. I put the rear up on two jack stands this weekend and ran the car up to between 25 and 30mph where the vibration is most noticeable. The vibration was there, so this now rules out any front end components. I could feel the vibration through the steering wheel when doing this, even though the vehicle was standing still...

Thanks,

Jim

LiCelsior

iTrader: (32)

well u could replace the filter or u can just clean it. http://www.lexls.com/tutorials/trans...anschange.html

python

iTrader: (4)

mounts or rear axles...check em,also check the driveline coupler

JimsGX

Done it all... Brand new driveshaft, rear axles, tranny mount, engine mounts, differential, differential mounts, exhaust Y pipe butterfly bracket...

PureDrifter

iTrader: (10)

i noticed rear tire balance wasn't on that list....?

JimsGX

haha... I have four brand new Michelin Primacy MXV4's on it with four brand new ES350 rims. 215/17/55's. I had them road force balanced twice on a Hunter 9700. The vibration was there with the old 15" stock tires (Michelin's w/ 5k miles on them) and rims as well though. I have four new rotors/calipers/sliders / slider bushings too.

I've truly run out of things to replace / consider here... My next step is to fly you out to the east coast and have you figure out what it is...

I made an appointment with Lexus for this Thursday to look at it but this would be their third attempt. I'm rethinking it and considering bringing it to a transmission shop instead.

Amskeptic

CV joints. They develop wear pockets. Since CVs also have to "expand" and "contract" based on drive angle, you get a very high frequency vibration.

For fun:
Jack the car at the differential.
Remove rear wheels, support the lower control arms (I used a couple of huge tree trunk sections) as close to the hub carrier as you can. Lower the car slowly until control arms are close to normal ride height. Make sure TRAC is off and ride height control too if you have air suspension. Rev engine to 1400-1600 rpm in Drive, throw it into neutral and feel/listen for vibration. Try also to bring engine up to proper rpm for speed indicated on speedometer in neutral and see if any change in vibration occurs. If vibration is still there, remove brake disks and repeat, sometimes an out-of-round ebrake drum surface will give a vibration even with the brake shoes correctly retracted. Finally, check for a rythmical longitudinal in/out of the half shafts as you run the engine at idle in Low. This is the typical CV joint symptom of the ***** climbing in and out of the wear pockets in the grooves. If you have a helper, have helper run the engine at 14-1600 rpm in drive and feel the control arms on each side of the car to see if you can narrow down the source of the vibration. With such nice quiet cars, it is devilishly difficult to cure these vibrations if others have removed driveshaft coupler bolts and "forgotten" that one of the three is heavy and has to be indexed to the correct flange hole, or of they did not index the driveshaft correctly at the splines, or index at the differential mounting. If you found the vibration came in and out with the engine in neutral as you revved it, a torque converter imbalance is a nifty PIA.
Colin

JimsGX

Thanks for the post... The rear axles/CV joints are new. The vibration seems to be coming from the center forward and its a very low rumble. It works its way into the steering wheel as well, even when sitting still with the rear wheels spinning up on jack stands. It is most prevalent between 25~30mph. It's still there when the transmission is put into neutral and the viehicle is allowed to spin down to in-between the 25~30mph range. Does it up on the jackstands as well as on the road. I used to have vibrations to the rear before changing out the axles, rear rotors, differential and differential mounts. I'm suspecting its from the drive shaft/propeller shaft forward. I had the local Lexus dealer install the new drive shaft, complete with carrier bearing and new isolator pads. Recently, an indy mechanic that I had look at it thought that it was coming from the front half of the split driveshaft. Since Lexus installed it a few short months ago, I'm having them look at the car again tomorrow.

Thanks

3UZFTE

Go with Lexus, it kind of seems that you have checked everything else. It is a factory drive shaft too right? That way if the problem persist you can just keep hounding them until they put their top dog on it. It really does seem like you have checked everything. Also, I would try removing the wheels all together and try it again. I know they are balanced, but just try reducing an element and see if it continues. They very well could have put on a different shaft, who knows.

JimsGX

Are there aftermarket new shafts? I paid full boat for a Lexus shaft. My reasoning for having the dealer do it in the first place was that I figured they had the best chance of getting it right by having the different weight bolts available to them and the SST to verify the angle was right. However it turns out, I'll be sure to post the result.

I'll mention taking the rear wheels off and running it up to the tech tomorrow.

Thanks

JimsGX

Update: Dealer wasn't able to find the root cause of the vibration today. They're pulling out the half shaft's and using the SST on the drive/propshaft tomorrow to verify the angle of the shaft in relation to the rear differential.

JimsGX

2nd Update: After working on the car on and off for three days, the mechanic at the Lexus dealer left me a voicemail today saying that he believes he's figured out the problem. The differential pinion gear alignment with the propeller shaft is way out of spec. He said it wasn't even close. He's ordering shims on Monday morning. He admitted that when he changed out the driveshaft a few months back, he didn't check the propshaft angle using the SST.

If this ends up being the cause of the vibration, it's probably the reason the differential blew in the first place. The problem may have existed back to when the car was manufactured for all I know.