Any Ideas??

**01SsRacing** · 01-07-2013, 06:49 AM

I just recently had all BRM lowering springs, lower control arm + the relocation brackets, tranny mount, and on car adj pan hard bar one sided rod end link. Im very happy with it all untill I get on the highway, Im getting a crazy vib from the mid to back of the car cant pin point it yet. the vib comes from 70 up and at WOT its real bad, also if I put the car into D not OverDrive its bad also but 1st and 2nd are smooth. If anyone has some ideas or might know something please let me know its driving me crazy!!

**98TransAmWs-6** · 01-07-2013, 07:14 AM

Did you tighten everything down to the correct specs? I would start by rechecking everything. In addition did you load the suspension for the LCAs and relocation brackets?

***SMWS6TA*** · 01-07-2013, 07:22 AM

In addiation to what Will stated - check you pinon angle on the yoke. If it is not set to -2* you will have what you're describing.

Lowering the vehicle will change the yoke pinon alignment.

**35th-ANV-SS** · 01-07-2013, 02:33 PM

Originally Posted by SMWS6TA

In addiation to what Will stated - check you pinon angle on the yoke. If it is not set to -2* you will have what you're describing.

This is what I was going to suggest. Lowering your car with adding that tranny mount has changed your pinion angle and that will destroy your drive train; u-joints and rear end. Hopefully you have an adjustable torque arm and if not, you should invest in one.

**01SsRacing** · 01-07-2013, 03:13 PM

everything was TQ to the derections, also was pre loaded.

**01SsRacing** · 01-07-2013, 03:16 PM

Originally Posted by 35th-ANV-SS

This is what I was going to suggest. Lowering your car with adding that tranny mount has changed your pinion angle and that will destroy your drive train; u-joints and rear end. Hopefully you have an adjustable torque arm and if not, you should invest in one.

I do not have a adj TQ arm still the stock one, and it might even be bent some. I dont know what the pinon angle is ill have to get that looked at. In all my reseach I didnt know lowering the car would effect that and JW what would the tranny mount have to do with it?

**35th-ANV-SS** · 01-07-2013, 03:24 PM

Your drive shaft comes out of your transmission. If the new mount is offset different (some are 1/8"), it throws the pinion angle off.

Lowering your car changes your car's suspension geometry - so again, this in addition to the above most likely changed your pinion angle.

Pinion angle simply refers to the angle of the differential's pinion in relation to the drive shaft. The torque arm controls the rotational degree of your rear end. An adjustable torque arm allows for you to change this setting. Stock setting is around -2 degrees. You can use a magnetic angle finder to measure it.

**01SsRacing** · 01-07-2013, 03:31 PM

Great info, so what do you think should be done first? Check the pinon angle see what its at? and if it off I need to buy the adj TQ arm, and what is a good angle setting for the car?

**98TransAmWs-6** · 01-07-2013, 04:29 PM

Originally Posted by 01SsRacing

Great info, so what do you think should be done first? Check the pinon angle see what its at? and if it off I need to buy the adj TQ arm, and what is a good angle setting for the car?

I would check the pinion angle before you do anything.

**35th-ANV-SS** · 01-07-2013, 09:16 PM

Different setups require different angles. Most range from -1.5 to -2 degrees though.

**01SsRacing** · 01-08-2013, 04:48 AM

so if it is somewhere within -1.5 and -2 thats not the problem?

**35th-ANV-SS** · 01-08-2013, 05:57 AM

I would say no, but I am guessing it won't measure that.

***SMWS6TA*** · 01-08-2013, 06:14 AM

make sure you measure it while the suspension is under load.

**01SsRacing** · 01-08-2013, 06:49 AM

Originally Posted by 35th-ANV-SS

I would say no, but I am guessing it won't measure that.

so you think its off then? and the could be my problem?

***SMWS6TA*** · 01-08-2013, 07:00 AM

yes

You stated that the Torque Arm might even be bent. All that will effect the geometry.

**01SsRacing** · 01-08-2013, 07:13 AM

Thanks guys!!! I hope thats it the vib is driving my crazy, I cant stand it.

that said any TQ arms you guys like some better than others?

***SMWS6TA*** · 01-08-2013, 07:57 AM

I'm using UMI Performance adjustable Full Length TA.

Very easy to install and one tough piece.

**35th-ANV-SS** · 01-08-2013, 07:59 AM

You can't use the one I run.

**01SsRacing** · 01-08-2013, 03:12 PM

I was looking at those and right now I dont have LT's will be getting some it was going to be next but I rather not trash my drive train if this is the prob so Ill get the TQ are next, but some I was looking at were saying will fit with LT's and others for stock, I dont want to buy anything twice cuz I only work part time haha money is tight.