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1983 Oldsmobile 98 Part Search and Transmission Help
I purchased a 1983 Oldsmobile Ninety Eight Regency Brougham 4 door about two years ago. It was originally elderly owner and garage kept up until about 5 years before I purchased it. When I bought it the odometer had only 54,299 Original miles only putting under 1000 miles in the last 5 years total and 20 over the last two of its time sitting.I have out about 8000 miles on it in the last two years loving and enjoying it.
Had to do a bunch to the car to get it back on road and been working on it ever since. According to the date stamp on the tires it still was running its original white walls on the front when I bought it. So as an indication it had not seen much tampering over the years and I had an pretty much all original car to work with. Got new brake lines, plugs wires, rebuilt carb, new water pump, 4 new shocks, 4 new tires, transmission flush, OD lockup solenoid, and many more little parts.
One of the main parts I am having trouble tracking down is the plastic/fiberglass rear bumper filler. I was hoping someone on here had a good suggestion other then the ones on ebay that I am skeptical about.
Also suggestions on Transmission issues, it shifted and operated fine the first drive after sitting. Drove it about 10 miles to a shop for inspections, then on the 10 mile drive home it started having a problem. Now it hasn't worsen over the last 8000 miles but other then the suggestions of a full rebuild haven't had any good suggestions to what the problem is.
So when the transmission is cold, it will shift into all the gears without issues. Kicks down with throttle when passing, after new OD solenoid engages lockup as well without issues. However once it warms up, say about a mile of stopping and starting out of my housing plan it wont shift cleanly into Second gear. Taking off at a reasonable speed it will attempt to shift at the normal time however will softly engage the gear not feeling like a full engagement. It will then pound into the gear only if the pedal is let up on, then everything is fine. If you take off on a hill going down, and coast up to speed for second gear shifts fine same as if you ease up to speed and don't put a lot of load on it. The fluid and filter was changed to attempt to resolve issues however only slightly improved over all shifts. When I bought the car I found the OD lockup solenoid was disconnected on side of the transmission. I drove it for about 1000 miles then decided one day to plug that in. Quickly I learned that was a bad idea when I had to drop pan again, replaced filter, fluid, and solenoid. That fixed lockup but still shifts issues.
If anyone has some suggestions please let me know! Thanks!!
I'll assume this car has the THM2004R trans. Check the TV (throttle valve) cable adjustment it may have been moved when the carb was off. There is a factory spec for initial adjustment. That's the cable from the carb linkage to the trans. There's a push button ratcheting adjuster up by the carb. Try a click or two tighter (push button in and pull cable away from the carb one click at a time. Road test after each adjustment). Careful, improper TV adjustments will fry a 200 in short order. Read up on this if your not sure what I'm describing.
What fluid did you use?
What did the original fluid look like?
How much "mud" was in the pan when the first change was performed?
Next step is to check the pressure of each hydraulic circuit and compare to the spec. Circuit pressure checks are the best way to check a transmissions health to determine if it needs a rebuild.
Did the solenoid get a new gasket and the proper torque when you installed it?
Disconnect the solenoid and see if the 1-2 upshift is any different?
The tv cable is the first thing I checked. I purchase the car from a friend so had full access to it before I bought it, and transmission issue occurred before it was mine. The only things that where done before the issue began was brake line, front caliper, new battery, and drove to get it inspected. It was on the drive back to his house it started acting up. With the shape, mileage, and price I bought it anyways. But the tv cable was moved slightly in and out making no difference other then making it worse. Made sure it wasn’t sticking then followed adjustment procedure. Pushed it all the way back till the cable end touches the adjuster, then pushed gas pedal to the floor. It came out and locked in position. After driving it about 150 miles and research I did notice the gas pedal wasn’t fully opening the throttle, so I clicked the cable out a little more and got a little better.That is the point I flushed the fluid, from what I could tell it had been flushed in past, seemed like a newer gasket style then what would have been on it and fastener heads looked like they had been taken out. Not stripped just signs of tools going into the heads. During the fluid and filter change I noticed the harness disconnected on side of transmission and the plug had been filled with some kind of putty. Not knowing a large amount of 80’s cars only having experience with 90’s and 2000’s I left it be until I could research. The fluid it self looked fair, seemed like I expected, red with some clutch material on pan. Nothing out of normal that I have seen, no big chunks, no metallic flakes or shavings. Honestly looked better then the fluid I changed in my 90 Grand Prix years before. Used typical gm dextron fluid, and filled it up. That made no difference to the shifts. This is around the time the carb hot rebuilt due to a bad mixture control solenoiD.
After carb rebuild it had driven over 1000 miles, the transmission problem did not get worse. Did a bunch of research and got a bunch of mixed answers to the wire harness on the side. Did learn it was for the od lockup but a few people told me it wouldn’t have that on my year. It would be vacuum controlled but judging by the fact the car had a harness I knew that was false. At this point I had the genius idea to plug it in. That was stupid, it did drive, and OD locked up, however quickly learned why it was disconnected. It wouldn’t unlock. Stalled at every stop on the way home. Ordered part and dropped pan. Replaces the solenoid with new gaskets, filter, and fluid. Things seemed great after that. Got lockup and until I made it out of my house plan seemed to shift better. Then heated up and problem was back. The problem hasnt gotten worse over the 7000 miles since that.
I have a theory the the original owners took the car to a transmission place due to lockup issue. They checked it, and told them it needed rebuild. Either they lied to them about rebuilding and just disconnected solenoid and flushed fluid or owners declined repairs. Not sure either way I know the second owner of car didn’t even know the solenoid was disconnected as over the 7 years of ownership only put around 1000 miles on it. Large part of time it sat in his driveway with a dead battery and expired inspection. So I don’t know for how long or how many miles it was driven with lockup disconnected. I do know over the last 20 years according to few history records I found it only went around 10,000 miles on total. In early 2000’s it had around 40,000 miles. I haven’t looked at tag on tranny to see if it is original or not but honestly with miles and condition I would imagine it is. I hope this answers all your questions. Thanks
Had similar issues with a Caprice of that vintage. Swore it needed transmission work and had two shops look at it and they both said only a rebuild would fix it. It was late fall in Minnesota and I new it was due for some delayed maintenance work too. Not having the money for a rebuild, but hoping to get through winter, decided to do a tune up. Turned out a new cap, rotor and coil fixed it.
Had similar issues with a Caprice of that vintage. Swore it needed transmission work and had two shops look at it and they both said only a rebuild would fix it. It was late fall in Minnesota and I new it was due for some delayed maintenance work too. Not having the money for a rebuild, but hoping to get through winter, decided to do a tune up. Turned out a new cap, rotor and coil fixed it.
Valid point Mark. Check for bad ignition components vacuum leaks etc...
83 sounds like its time to dig into a manual for the car. Get a good Chilton manual and a good THM2004R manual with a good troubleshooting guide. I'm not sure if an 83, 98 has vac or electronic lockup control. My 83 GMC had the vacuum solenoid with a 700R4. But my 87 GMC had the electronic lockup on the 700.
Step back and start from the very beginning. Your experiencing trouble with the lock-up function of the converter and have a 1-2 upshift problem
Is the upshift best described as a bump slide 1-2 upshift, a delayed 1-2 upshift or a slipping upshift?
How are FULL WOT throttle upshifts??? How are the downshifts???
Heat seems to play a factor as well. That means the fluid viscosity is somewhat thinner hot than at ambient. This points to a cross leak. A leak can occur anywhere, seals, valve body, servo seals, broken spring somewhere etc...The pressure check will zero in on which circuit.
Again without hydraulic line pressure readings, we are playing a guessing game. We need those pressure readings first. A reliable trans shop should be able to perform this simple diagnostic test for a half or one hour of labor.
A rebuild kit is relatively cheap for a 200. Its not that hard to rebuild with some good mechanical knowledge decent tool set trans jack and a CD showing step by step instructions. The biggest challenge is having the right sized snap ring retainer removal tool to get the drum out(rent or fab or buy, not too expensive) and getting the friction n steel stack tolerance just right. Use compressed air to actuate the stack on the bench and measure with feeler gauges. Make sure you have the exact kit for the trans. I like to do all of the sleeve bearings while it's apart too(similar to cam bearings and installed the same way.
Contact Art Carr, TCI or Trans Star for parts, kits, tools, CDs and general advice.
Did you ever find bumper fillers? I replaced mine with fiberglass, one piece, no seam in the center. They look OEM and came out very well even though it was a PIA. I bought them from a fabricator in Alabama. I would like to know your source for Brake lines if you don't mind share your source. Thanks, Brady Rear, one piece fiberglass filler with no seam like most after market fillers.
December 20th, 2017, 08:37 PM
