I have a 1986 firebird that I pulled the motor and tranny of, now that I have the tranny out how do I tell what type of tranny it is. I want to put a 350 in it with a 700r4. How do I tell if the one I have already isn't a 700r4?

 

How many gears do you have? 700R4 is an overdrive tranny, it has 4. Versions of the TH350, TH400, and 200C have 3 gears. Also if you can find some pics, the fluid pans are sized/shaped different.

 

The 700 has a basically square pan with 16 attaching bolts.

 

These are some quick pictures I got for now where the engine and tranny are in the back of my truck. I hope this helps, if not I'll get better ones later today. I'm pretty sure it has overdrive, oh and it is marked MD8 on the side. Thanks.

 

After doing some research on the internet, it looks like is a th700-r4. RPO code MD8, ID # 6yxm142b. Can anyone give me anymore information on it?

 

it's a 700r, but it appears to be an older truck model.
- I can't see the casting "rainbow" tell-tale for it to be the later model(but it's hard to tell through the grime), and it appears to have the large bolt holes for the aluminum converter cover, thus making it the truck case.
- The truck case would be a good thing, but if it's the early model 700, it won't hold as much power.

clean off the area behind/around the dipstick tube and see if it has a "rainbow" casting line on the case

 

The code breaks down to:
6 1986
yxm 2.8 liter multiport f-body
142 is the julien date it was built
b built during the first shift of the day

 

hummm, after a closer look at the picture, it may be the 60 degree bellhousing... 86 model 60 degree bell trans? wonder if it's "too heavy" for the trash men to pick up......

 

MD8 means it is a 4L60 - a later model version of the 700 R4. It will NOT mate with a 350. The 4L60 is a trans in high demand since it mates with the 2.8 and the boosted versions, 3.1, 3.4 so you should be able to either swap it for a 700 R4 from a 350 or sell it and buy a 700 R4 from a 350. Good luck!

 

Heh - Interesting to hear that - I've had an 'MD8'-marked 700R4 behind the L98 in my GTA since the day I bought it...