arod231

If anyone can help I would be greatful. I need help decoding my transmission to see if it is for a v6 or v8 engine. I took out a T5 manual and 305 tbi and swapping in a 350 carb and I bought a 700r4 from someone that said it was behind a v8, anyway here is the numbers 14TM151C, MD8, and 8663549. I think the first number means that is 1991 built 151 day of the year at night shift, the second number just means it's 4l60 or 700r4 having trouble with third number,please help someone.

DeathStarr89

iTrader: (1)

Just snap a picture of the bellhousing, that's the fastest way of knowing.

92RS_Ttop

iTrader: (3)

What he said. They look very different.

novaderrik

if the bellhousing is about 18" across, then it's a V8 trans... if it's closer to a foot across, then it's a V6..

RubberDucky

iTrader: (4)

V6 bellhousing is more of a trapezoidal shape.

vetteoz

iTrader: (13)

http://en.wikipedia.org/wiki/List_of_GM_bellhousing_patterns

arod231

Here is a pic of bellhousing

sofakingdom

iTrader: (1)

V8

92RS_Ttop

iTrader: (3)

Yep, V8.

arod231

Thank you all for the help that was a relief.

morgsie

iTrader: (1)

It could have come behind a 4.3L V6...

arod231

If it was for a 4.3 v6 could you rebuild it like a v8 and have the same internals in it?

fasteddi

iTrader: (2)

I dont see why not. The guts on a 60* V6 700r4 are almost all exactly the same.

arod231

Thanks for all the help everyone god bless.

DeathStarr89

iTrader: (1)

Does it have the Fbody tailshaft?

arod231

Will have to send a pic tomorrow.

arod231

here are some pisc of tailshaft not sure about the different sizes of them. If someone can tell me if this is a fbody tailshaft.

morgsie

iTrader: (1)

Of course. Valve body calibration (shift points) are most likely different compared to the V8. Clutch stack ups might be different as well.

antoine

Its a f body tailshaft and v6 and v8 the internals are the same

greggbruce

iTrader: (1)

usually there's one less friction disc in each clutch pack if it's a v-6, to make it a v-8 you have to change the piston in that drum (to make it shorter) so you can add another friction and steel in that clutch pack.

if you are making more power than stock, I would suggest making it like a v-8.

trans by your code would be a '91 4TM. I am trying to find out what it was in.

are you POSITIVE it is a '4' TM -- an FTM they are telling me is out of firebird or camaro 5.0 -- they don't show a 4TM.....

antoine

The internal s are the same v6 or v8 look up rebuild kit it the same.

fasteddi

iTrader: (2)

The servo, boost valve, and intermet. valve are different. Smaller. At least this is true with 60* 700r4's

I know this because of adding in a shift kit and relizing that every part was too tiny for a trans go's reprograming kit.

greggbruce

iTrader: (1)

yes the kits are the same, but you have left over parts for the v6. I have overhauled hundreds of these, the 6's are different than the 8's.

arod231

My bad, yeah it is a f and not a 4. Thanks it was really dirty and I looked at it wrong

arod231

This is the best website to do anything with your third gen fbody, because it has the best people, so many bright minds. Can't thank you all enough.

greggbruce

iTrader: (1)

SCORE !!! an f body trans for an f body car !!!

DeathStarr89

iTrader: (1)

Yep, not a V6 trans of any kind.


I'd upgrade a few things while you have it out, It's not that bad to do on your own.


I'm putting about 350 HP/300TQ to a V6 700R4, spinning it to 7K RPM and it's taking it like a champ with the street/strip kit from Pro Built Automatics and a 4500 stall.

https://www.700r4l60e.com/store/prod...&cat=52&page=1

fasteddi

iTrader: (2)

Mines good to go also with the trans go reprogramming kit, vette servo, larger intermediate and boost valve from probuilt. Id bet im right there with deathstar pushing 300+hp and more then that on Tq on a 3k stall up to 6500 rpms. And the ole 700r works fine.

Just read up and be patient. It was my first time working on the trans department and it was flustrating at times.

antoine

http://www.700r4l60e.com/forum/viewtopic.php?f=6&t=108

project89

iTrader: (1)

i was going to say when i was building my v6 transmissions to live behind my turbocharged 3.1 that i never had any leftover parts

i used the tci master race rebuild kits on mine

fasteddi

iTrader: (2)

I didnt have left over parts, just parts that the insturctions said dont use. So I had to buy different parts so that I had ones that were "ok' to use with the kit.

greggbruce

iTrader: (1)

that link talks about an "E" transmission.....

I've spent 17 years in a GM dealership building transmissions, I can't count the number of v-6 trannies that have one less clutch in each drum, and I have the stacks of extra clutches to prove it. I also cannot count the number of pistons I have changed to convert v-6 to v-8.

it's really no big deal...

greggbruce

iTrader: (1)

LOL -- so they really weren't 'left over'?

arod231

It would be my first rebuild on my own. I've helped and watched someone rebuild a 700r4 but just back to stock specs. I haven't decided if I want to tackle it by myself or not yet.

arod231

Before I can even think about rebuilding the transmission got to rebuild my 350 carb engine.

morgsie

iTrader: (1)

greg, it would be cool to have a list of what the 3 letter code corresponds to what car it came out of. I know YMD is Corvette, and that's about it. Can you share your list (if you have one)?

And yes the F-body valve body is one of the better performance ones. My '89 Caprice cop car had an almost identical VB to what came out of the F-body's. Shift valves stamped: M (1-2), 10 (2-3), 0 (3-4)

greggbruce

iTrader: (1)

I prodded a friend at the dealer to dig up some stuff.... I had a small list (like only a couple years) once upon a time, but seem to have misplaced it, sorry. If it turns up, I will post it.

I know a couple by memory from my dealership days: TAD is a baby blazer (but 4L60E)
and a KCD is a full size truck (4L60E)

greggbruce

iTrader: (1)

I've taught a couple of people, not too awful difficult, just like a puzzle that you can't leave any parts out of--- neat part is, you get to start with the puzzle already assembled, and take it apart ....

morgsie

iTrader: (1)

Would be cool if someone kept a running list of known codes... But as long as you know what shift valves to look for you can easily locate the right valve body from a used parts supplier.

I come from a pretty broad mechanical background (cars, helicopters and now elevators), but was very satisfying (and frustrating at times) rebuilding my 700R4 and having it work (so far). Learning curve was pretty steep having only changed filters, fluid, and a few TV cables and lockup solenoids in the past. Very rewarding and would have no problem rebuilding another automatic in the future.