Which Transmission

[Baron Von Buick]

How do i find out which Transmission is on my car? Someone told me that there were 2 different trans. options on my Regal the year they came out? He said one is good and the other one is total crap so id like to know. Its a 1984 Regal N/A NOT limited.

Thanks
Patrick

 

[Ttype83]

On the passenger side back of the trans is a metal plate.
This numbers tell you where and when the trans was made plus the model of that trans. Do you have a 350 or 200r4 ?

Jim

 

[b4black]

The OD trans (200-4R) was only available with the 3.8 Turbo or 4.1 V6. I doubt he has a 350C, but he might. It's probably a 200 or 250 or somethng like that.

 

[Ttype83]

Originally posted by b4black
It's probably a 200 or 250 or somethng like that.

I think if had had any of those 2 trans I would go with a 350 swap. A quick trip to the u-pull it, fly wheel, TC, trans and it should be a pretty easy swap don't you think Rich?

 

[b4black]

I'd beat on whatever it is 'til it died. Then I'd either get the 350C or more likely a 200-4R, becuase the OD is very nice. Then a 3.73 rear from a Monte SS would be next. An '85 Regal will already have the frame mount for the 200-4R crossmember.

 

[turbofish38]

Acoording to my information you could have either a THM200C or a THM250C. Never have figured out why they used two different trans for the same engine. An easy way to tell is the THM200C used a one piece transmission case and the THM250C had a seperate tailshaft extension. Also the 250C uses a vacuum modulator and the 200C didn't. Also a 250C can be built up to 350C specs if you have the parts as the only difference is the 350 has extra plates in its clutch packs. I also have been reading where the 200 and 200C are the prefered trans for the Stock Eliminator classes if you are running a 4 or V-6 as they can take 300 lb.ft. of torque and weigh less than any other automatic trans. Eric Fisher

 

[turbofish38]

Hey I forgot. If all this fails look for option codes MV9(THM200C) or M31(THM250C) on the option tag on the bottom of you deck lid. 1984 was the first year they started using the service parts indentifaction label. Eric

 

[Baron Von Buick]

Thanks guys you are all a big help, But i've had a mechanic tell me that the 200c is total crap, unreliable and overall junk. is there a reason why he would say this? he wasnt trying to get money out of me for a new trans because i just bought an intake from him and he was telling me how to hook up the 3.8 and he told me "If you have the 200c its total crap and not worth putting a shift kit into" Thanks for any info

Patrick

 

[Ttype83]

Each of us have something that we hate and think is crap....
Mine: chevy 305,307 engines are crap and Comp cams service.
Others feel the same about other products, hence him saying the 200c is crap.
JMO
HTH
Jim

 

[Turbo Loyd]

TH 200C

My understanding the earlier TH 200C transmission were not particulary good, but by 84 they were decent.

The TH200C shares many internal componets with the TH 200 4R except the overdrive. Any good 200 4R transmission builder can make the 200C reliable, plus it is lighter therefore less HP loss.

 

[bakerlaw67]

Gotta agree about the crapworthiness of the TH200. I went through two on my '78 Regal with the whopping 145 hp 305 Chevy w/a 2bbl. I never understood the logic of further crippling the motor with a junk trans. I was really peeved when a friend got a '79 Regal with Pontiac 301 4 bbl and a TH350. (It didn't help that he had buckets, console, T-tops and rallyes - and I didn't) That car moved.

It just occurred to me that the combo might be a wicked turbo conversion (just a wee bit heavy under the hood).

 

[turbofish38]

I can remember when my GN was new and everybody said the THM200-4R was a piece of crap. Now there is enough parts and technology out there to make these things bulletproof. And I'm sure there is some old fart out there that can say" when my 49 Roadmaster was new everybody said the Dynaflow was a piece of crap. An interesting tidbit I might add is that when GM changed the model designation on their transmissions from i.e. THM700-R4 to 4L60E, do you know what the number stands for? In this example the 60 is actually 600 and it stands for how much torque the transmission can handle for one second before it fails, hence 600 lb/ft of torque for one second. I have no torque figures for transmissions built before 1990. Eric

 

[b4black]

Look, with OD, you can run much steeper gears, better MPG and easier cruising down the hiway. If you buy that arguement, than a 200-4R is the logical choice. 350, 250, or 200 becomes moot.