GV Under/Overdrive Units

I have several, the oldest one is in the PW, which has been in there since 1990 something.

In that particular use it was used for the bad 3/4 split in the 435 trans, it also wound up paying for itself in mpg gained in 1 year (PW had 4.5), back in the early 90's when gas was far from these prices.

I had installed one in my RR (4.3) and Mag (4.8), RR in the 550hp are the other 800 + 2 stgs.

None of them have any issues.

The thing you'll like is you'll be able to split gears in the trans rather than just have what you have and a od gear thrown on the end, you'll find it useful in certain situations.

Shaft will need to be shortened, or get a new one in AL, what i did with all of them even the truck.
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