Mechanics

ENGINE TEMP NORMAL, BUT TRANNY RUNNING HOT

1999 Oldsmobile Intrigue • 110,000 miles

Reasonably well-maintained car. Runs and performs well. Engine temp seems fine, and temp gauge seems to work correctly, never exceding even the halfway mark on the hottest days, and usually its about 35% to 40%. A couple of years ago, during warm months, I began to encounter very hard transmission shifting -- like with a real jerk -- in all gears as best I can recall. Felt like hot tranny problem to me, but I'm no expert. Attempted to drive at steady pace to minimize stops and starts. Found that I could drive five miles with no problem, park for an hour, start up and the hard shifts would be present. Finally, hit upon a very suboptimal and only partial solution. For the last two years, I have the A/C on at all times all year long. What this accomplishes is that the two cooling fans now run every second the car is on. Engine temp and temp gauge still seem to coincide. Appears to me that tranny temp is the issue, and the constant flow of air from the fans cools the tranny. So, now almost all of the time (except on the very hottest days, the tranny shifts without incident. No doubt the tranny has encountered some excess wear, but note that fluid has good color and the fluid does not smell burned. Generally, I only drive a few hundred miles a month, although last year, drove a 1,600 mile trip to the south with air temps in the 80's and 90's with no incident.

Any thoughts, ideas, suggestions, clues would be appreciated. I'm in my sixties, and pretty much past the point where I am able to do major, heavy automotive work in my garage, but I have no problem crawling under a properly supported vehicle and getting into stuff -- just not too much energy for wasted effort working on a car. Clearly, this vehicle is not worth much expense for professional repair, and, fortunately, I've been mostly able to avoid that about 45 years.

Thanks, guys.

Roger
Avatar
Rogersintrigue
April 30, 2012.



If trans cooler is in radiator then you could try rerouting it to an external cooler?

Tiny
Fixitmr
Apr 30, 2012.
Thank you for suggesting an external cooler. What would you suppose is the problem with the internal cooler located in the radiator? Could it be clogged? If so, could I unclog it somehow by disconnecting both cooling lines? If so, how or with what product? Air pressure at 40 to 60PSI, or maybe a chemical. Perhaps the cooling lines are partially clogged -- any thoughts on that? Or what about the radiator in the vicinity of the internal cooler? Any chance that there is some clog in that vicinity? Thanks again

Tiny
Rogersintrigue
Apr 30, 2012.
You can check cooler flow by disconnecting 1 hose and start car for a second. Should squirt out pretty fast. I just suggested external cooler because it does not ADD heat to the fluid. Although sitting idling may defeat that advantage.

Tiny
Fixitmr
May 1, 2012.