96 Corolla Overheating or Auto Transmission Fluid?!

Hello Everyone,

I’ve been driving a 96 Corolla into the ground for the past 5 or 6 years and recently it’s been having overheating issues. It has overheated to the point of steam twice now, and I’m worried at this point I’ve fried the engine or transmission.

I regularly check the radiator fluids and oil thinking that these would solve the issue, but alas it happened again today ten fold.

While driving home in hot southern california today I first noticed my transmission slipping in traffic. It was slipping when I started moving in stop and go, and settled in once I was going 30 or 40 miles per hour. I had my puppy in the car and was only a few minutes from home so I thought it would be fine, otherwise I would have pulled over immediately.
As I got closer the problem got worse to the point where I could no longer shift and move forward. I over revved the engine to get it into a safe spot and it overheated. After waiting 40 minutes I checked on the Transmission fluid (checked unrunning) and it was bone dry. The radiator was full with coolant and oil levels looked good. I put as much transmission fluid as I had in my trunk (not much) back into the car, started it and got the car up the few more blocks I had to go. On the way it was still slipping, at the severity it had to begin with.

My question to you is do you think the transmission is totally shot and I need an overhaul? Or is there some hope that it may have been overheating because it needs a flush/drain and new transmission fluid? The car is at 136k miles and has had a replaced radiator in the past year.

Thank you!

If the engine was severly overheated the transmission was severly overheated. So the engine/transmission are both fried.

Tester

All that heat of the slipping transmission clutches was going into the cooling system via the transmission oil cooler in the bottom tank of the radiator. That sent boiling hot water into the water pump, engine block, and head. It is no wonder that you were steaming.

Whether the transmission slippage was a result of the low fluid level; a severely neglected transmission; or just wear and tear, is moot at this point. The transmission is finished. A pan drop, filter change, and fluid exchange might get you a few more miles but I would not trust it for a long drive anymore.

Consider this Corolla “…driven into the ground” and move on to your next dream vehicle. You would be throwing good money after bad to try to resurrect this Corolla.

I think the transmission is gone and the engine a heartbeat behind it. It’s time to move on to another car.

If you are determined to get this Corolla a few more miles down the road, here is what you might do. Drain the transmission, drop the pan, clean the pan, change the screen/filter, and refill the pan up to the ‘Hot’ line on the dipstick (transmission hot).

Now drive it around with the shifter in manual low. If there is no slippage and/or overheating, do the same in manual 2nd. If it is okey there, try manual third i.e. with the OD button ‘OFF’. Finally, try it with the OD button ‘ON’. If you get overheating and/or slippage in any manual gear selection go down to the next lower manual gear. If you get slippage and/or overheating in manual low, there is nothing much else you can do. Continue driving in that gear until you can no longer stand the engine noise or the engine disintegrates. IIRC the Corolla does not have a tachometer but if it does keep the RPM short of the yellow arc and/or red line.

Another option is to buy a used Japanese engine/transmission combination. I have not priced a combined unit but it may be less than the KBB of your car in stated condition. Also some jobbers will install for a reasonable price. There probably is a great crop of 1996 Corolla engine/transmissions coming from Japan at this time.

Make sure the radiator fan is spinning when it overheats. The car’s cooling system - even if it is workin correctly – is not designed to cool the engine enough at low speeds and idling without the help of the electric radiator fan. If its not spinning when the engine is overheating, that needs to be fixed first.