mopower440

I was looking on car-part.com and LKQ for transmissions for my 1999 silverado extended cab shortbed 4x4 with 4.8, They show that something is different if it had a 4.8 than a 5.3 for that year (1999), what the hell would be the difference? 1999 4.8 vs 5.3, different trans..? (talking automatic, 4l60e) Surely they didnt use a different 4l60e behind the 5.3 than the 4.8 for 1999....?anyone know..?

I just looked some more and they have them different from the 4.8 to 5.3 from 1999-02, then 2003-07 classic, shows the same trans behind 4.8 and 5.3..so what would they change depending if it was behind a 4.8 or 5.3 from 1999-02? I thought it would be the same trans no matter if was behind a 4.8 or 5.3..?

Just looked on ebay, same thing, punched in 1999 silverado automatic 4x4 transmission, it shows ads for on4 for the 4.8, and some for the 5.3, but NONE say they interchange...??? So how is everyone doing engine swaps without doing transmission swaps also? For instance, in a 1999 silverado with 4.8, you want to swap in a 5.3, it wont work with the 4.8 trans? WHY?

gamble686

iTrader: (3)

Didn't have any difference that I have noticed between mine and my buddies 99 5.3. However, have you considered an 80e swap? I find 80k mile 80e on Car-part.com all the time for about $500.

mopower440

No, not needing one yet, just see they act like theres a difference and cant figure out why..