Thread: Downshifting an automatic trans

Originally Posted by Sabrewings

3 is for towing. 1 and 2 are for engine braking. When you pull it down into those gears, it uses different internal mechanisms called manual bands instead of the clutch packs. They are designed to provide engine braking with higher line pressure than you could use the standard clutch packs for.

When you leave it in D or 3, the tranny uses its first or second gear clutch packs to use those gears instead of the manual bands.

Trannyman probably has a more eloquent way of putting it, and he can surely show you pictures of toasted manual bands from people doing like you're doing.

sounds pretty complicated. lol. would this apply to every car or only GTPs? cuz i did this with my old grand am and never had a problem.

Originally Posted by Sabrewings

Depends on the transmission. This for sure applies to any car with the 4T65E. Grand Prixs, Impalas, Monte Carlos, Regals, etc. I think the Grand Am has the 4T40E, which I haven't paid much attention to.

oh. and it was a 93 grand am with a 4cyl. lol. wasnt the quickest car