Trying to make a 2004R transmission choice, 3OM (1983) diesel 350 Olds, or 5OG (1985) 307 Olds ? Engine will be 69 Olds 350, 310 HP stock build in a 41 Olds 2 dr Fastback. The 83 diesel trans looks like it may have never been rebuilt since all the plastic tags are still on the case, and fluid drain was fairly clean. The 85 307 trans looks like it has lots of miles, filthy trans fluid and some water came out when drained. I had some internal rust on some hard parts. I am thinking the hard parts are the same and just a different valve body, governor, accumulator calibration, etc. I thought I could start with the 307 version of different valve body, governor, accumulator calibration, etc. but on the diesel trans. However there were probably some internal improvements made between 83 and 85. I plan to use a hardened shell and good quality bands, frictions, etc. Does any one know of rebuilding a diesel trans for a gas engine?
http://www.cpttransmission.com call art carr he will set you straight as for which is the best option
Until today I never knew they were used on the diesels. If it is cleaner, that is the one I would use.
If one had water in it , I'd use the other one. I'd use a shift re-calibration kit ( not to be confused with a shift kit), and the gas trans governor. You don't want to mess with tuning the governor, seeing it's inside the pan.
I worked for olds dealer back in the 80's and I don't remember any 2004r in a diesel,I do remember a turbo hydro 200 that was not an over drive.
That diesel wasn't designed to be or noted as a power house so I wonder if it had anything special inside. I had a 310 350R in my 69 Cutlass that I special ordered in late 68 when I was in Vietnam. Loved that car and you will enjoy that engine. If you have't gone though it all the way make sure it has a metal timing gear in it though. That is the only problem I have had with a 350R and I ran one in my 51 Merc for a lot of miles. Come to think of it I have probably run more of those engine over the years than any other.
Although I have never done a full trans rebuild, I have tuned the governor and valve body, accumulator and servo's before with moderate success. I just welded a drain plug in, still a bit messy as the torque converter would keep draining the entire time I had the pan off
The TH-200-4R has a 2.74:1 first gear ratio, and overdrive is 0.67:1. Its odd-shaped 16-bolt pan has 13mm bolt heads. The TH-200-4R was used in GM rear-wheel-drive cars equipped with the 231 Buick, 301 Pontiac, and the Oldsmobile 307, 350 gas and 350 diesel engines from 1981-'90; however, many Chevrolet 267 and 305 V-8s also used the TH-200-4R because of the multi-fit bellhousing. You can find a donor TH-200-4R in one of these cars: I stand corrected
senginc you might find this page interesting. it tells what goes with what engine/trans wise http://tech.oldsgmail.com/eng_useage.php
The chart shows a 260 cu in V 6 diesel and a 350 cu in V 8 diesel. I seem to recall there being a 260 cu in V 8 gas Olds engine......which may been converted to diesel......but I sure as heck do not recall Olds ever using a V 6 diesel of any displacement. Since that chart does not appear to be an official Olds/GM publication, I am thinking the V 6 reference to a diesel is is error......or am I?
Do you think the 83 case and internals should be the same as the 85 or were there many internal or case changes between those years ?
No, there is a V6 diesel. Olds V8 block with two cylinders lopped off. Incredibly rare. As I understand it the newer the 200R4 the better, the more they were improved inside. I know as a kid it only took about 30,000 miles of beating on a 1984 - with the 307 - to kill it. Granted some of that was towing other cars with the Buick Electra it was in, but still.
You want the latest model 200R4 you can find. The real earlier ones, 1982-1984 have poor calibrations. (slide bump shift from 1-2 etc.), although a reprograming kit will correct that. 1985 and up gets better. 1986-1987 are the best version. They have the best calibration and a hardened sun shell and hardened stator support, also the rear planetary has a needle thrust bearing instead of a plastic washer and a modified forward clutch piston. All 2004Rs, no matter what year, had a 7 vane pump and should be converted to a 10 vane pump while rebuilding. Although all that stuff can be updated in earlier units, it costs more $$ to get it there. Find your self a Grand National or Monte SS trans from 1986-87 if possible. They are the best version. Bill
One of the top T-200/T-200-4R transmission builders - https://www.scottmcclayengineering.com/ He started out with building the three speed version, but the 4 speed is very much the same trans. with the addition of the fourth gear drum and internal oil circuits. I have two of Scott's transmissions with brakes in them. I also have one of Art Carrs in a more streetable car. Both of these guys dyno test their transmissions before they leave the shop. Mike
I opened up the 83 diesel trans. The valve body does not have the 4th gear switch, the port has a threaded plug. Instead it has a pressure switch on the 1-2 accumulator housing (pics attached). I am guessing it was probably intended to lock up in 2nd, 3rd and 4th. I have wired a 3 position toggle switch on other cars that I ran a 2004R and toggle switch up position allows the normal 4th gear lockup, center off position gives no power to lockup solenoid, down position bypasses the 4th switch (the 4th gear switch, has to be normally open and close when in 4th) and it locks up on 2nd, 3rd and 4th. I always wire through a 2 pole brake switch that opens power to the lockup when the brake pedal is depressed. (the 4th gear switch, has to be normally open and close when in 4th for this circuit)
Yes, you can use a comb. cruise and brake light switch to open that circuit. Of course, when using the 4th only port, the lock up comes off, once the trans downshifts, coming to a stop. Also , GM made a vacuum sensitive switch that you can mount in that feed circuit . It knocks the l/u out for I think 10-15 seconds when you step on the gas pedal quickly. It can be found on mid 80's C10's among other places.
You have to have a now rare plastic vacuum valve to get the delay (was on 80's S10's), otherwise the vacuum switch will make the trans go in and out of lockup oscillating quickly under certain load conditions. If you have a low rear axle gear you don't need the vacuum switch (my 41 and 42 Olds have either 3:90 or 4:11 factory rear axle)
My 42 Olds Ute has 307 and 200-4 R that came out of a 89 Cadillac Brougham. Best shifting 2004R I ever had (engine and trans never been apart). [
I have used this kit a few times 20 yrs ago. 200-4R 2004R Transmission TRANSGO Shift Kit https://www.amazon.com/200-4R-2004R-Transmission-TRANSGO-Shift/dp/B01H49MPQG Seems like it can be setup as reprogramming (update) and still have normal shift feel. Any other reprogamming kits out there ?
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