Here is another one of those questions, wondering if anyone out there has "been there done that."

I have been offered a good price on a Gear Venders Over/under drive unit (new) and was thinking about doing it. I am running 4:10's now and doing a reasonable amount of towing (32' Fifthwheel). Not that I am having any problems mind you, but it sounds nice. I was wondering if anyone has such a unit on their trucks (not motorhomes) and what their experience has been like?

 

I ran a GV overdrive for 15 years behind a 460 gas motor and a C6 transmission with 4.10 gears. It worked great for that application. It has a gear ratio of .78:1 which gives a final drive of 3.20 with 4.10 gears.
If you have a 5 speed TorqShift, I think that it would be useless except for getting a double overdrive ratio of around 2.24. The TorqShift has about a .75:1 gear split from the factory and I would guess that the 6 speed manual is that close as well so I'm thinking you would be just duplicating all your present gears. If you do get it , do NOT use the GV overdrive for compression braking, it's very hard on the cone clutch in the unit.

 

I read a post on another sight were a guy installed one on a 6.0. He said it didnt have the gear splitting ability, due to the TQ Shift being a close ratio transmission. It only gave him an extra overdrive gear ( double overdrive). he said it brought his rpm down to somewhere in the 1900 @90 MPH range. He liked it and said he would do it again.

 

What gears was he running in the rear end. I have th 4:10 and was thinking of changing them to the 3:73 until I was offered the GV unit. Havent do a thing yet. I notice my gears run about 2000 rpm and just under 65mph. I wouldn't mind having that lower.