auto trans change
Thread Starter
Instructor
Joined: Oct 2010
Posts: 118
Likes: 0
From: Rapid City South Dakota
auto trans change
Hey y'all,
I need to get my tranny rebuilt but had the idea of changing from a 3 speed auto to a 4 speed auto. Who here has done this? Other than the actual tranny what where you running into for costs? Its a 78 L48.
Thanks,
Dano
I need to get my tranny rebuilt but had the idea of changing from a 3 speed auto to a 4 speed auto. Who here has done this? Other than the actual tranny what where you running into for costs? Its a 78 L48.
Thanks,
Dano
Instructor
Joined: Aug 2011
Posts: 135
Likes: 0
From: London, Ontario
I have been thinking about doing the same project. I have considered both the 200r4 that was in the Buick Grand Nationals and the 700r4 that was in everything else GM made RWD. I think you would want to put a shift kit in it, depending on condition you might to rebuild it as well. Could be anywhere from 500 to 1000 depending on what the trans needs. You will need to remove the old trans, modify your cross member (or replace entirely) and you'll need your original bell housing for the 200r4 I believe... correct me if I'm wrong. So to buy the trans 200-400, rebuild and install shift kit 500-1000 and labor costs to swap them and modify the cross member $500.00 Those are loose ball park figures, you might find a tranny shop that will do everything for cheaper. Good luck and let me know what you come up with.
Burning Brakes
Joined: May 2008
Posts: 1,116
Likes: 5
From: Middleburg Florida
Dano,
This has been done many, many times. 2004Rs, 700's, 4l60E's all of them. The 200's don't need a new drive shaft, the others do. All need some cross member modifications (or you can buy a cross member for around $300). All can be built to handle about any horsepower you might have. A good quality kit for a 200 is about $350 all in. You can probably find a core for around $100, look for a company in your area maybe contact the bone yards for who handles cores. Cores are much cheaper than used functional transmissions. The biggest challanges are the torque converter lock up and the TV cable set ups, and those aren't hard either, and there's lots of options for them. Like anything else, you can spend as much as you want. Do some searches and you'll find many threads on the subject.
This has been done many, many times. 2004Rs, 700's, 4l60E's all of them. The 200's don't need a new drive shaft, the others do. All need some cross member modifications (or you can buy a cross member for around $300). All can be built to handle about any horsepower you might have. A good quality kit for a 200 is about $350 all in. You can probably find a core for around $100, look for a company in your area maybe contact the bone yards for who handles cores. Cores are much cheaper than used functional transmissions. The biggest challanges are the torque converter lock up and the TV cable set ups, and those aren't hard either, and there's lots of options for them. Like anything else, you can spend as much as you want. Do some searches and you'll find many threads on the subject.
