I installed the 4.10 gear with posi trac (daily driver). IT made a big differance in RPM and power. I ajusted my super chips programmer for the gear.

The problem I am having is at 90MPH I get a buzz or harmonic vibration, whenit hits 100MPH its gone then comes back at 90MPH and is fine below 90MPH. Has anyone herd this before?

I talked to Pyle Brothers the guys that installed the gear and posi,theysay their is nothing in the rear end that can make a vibration at 90MPH.

So I got a second opinon and the guy at Green & White says he has the 4.10 gear and it will do that at that speed because it is spinning its *** off. Should I have installed the race posi?

 

I don't know about the race posi, but if you have a vibration that shows up only at certain speed, then you may have a wrong size shim issue. These have to be correct within .001 of an inch. I would not be suprised if they have to redo it.

 

Pyle Brothers I have herd from many shops that they are the best when it comes todifferental rear ends. PB is a race shop that works on race cars and trucks & pro-stock. I watched this guy for 4hours install the 4.10 and posi and it looked professional.

New seals, berrings, the entire rear end was gutted. Not sure about a different scim.

 

What brand posi?

 

Dura Grip 8.5 30s

 

I am unfamiliar with that brand. Sorry, but, no advise here.

 

Damn!

 

[:@][:@][:@][:@]

 

You know my Supra came stock with 4.30 rear end gears.

 

I've heard of rear ends "singing" before. It was always a fluid and/or manufacturing issue. (Ex. Some gears just make noise period.) Depends on how bad it is I guess.