DanStew

I am trying to help a buddy of mine. He is stuck out of town with his i think 92 4runner. It is the standard 3.0 with auto tranny. He called yesterday saying the tranny temp light came on. I went though it with him over the phone and after a while of realizing the white smoek is not a head gasket but the tranny he got it towed. well it is still out of town and the mechanic said it was the 4th gear of the tranny. The oil in the tranny doesnt smell burnt to him. Do you think he did bad damage to the transmision if he cought it in time? His truck just has 31s on it, but he was running in high elevations with hills on the freeway. Mechanic says he can drive back without over drive. If he can get it back and baby it around will the 4th gear clean up and he can get back to normal in areas that are not as extreme elevation changes? I am trying to get him to keep the 4runner, he doeasnt want to get rid of it, but he is at the cusp since we found some rust on it a week or so ago. But he says the mechanic is going to charge abotu 1200 for a junkyard tranny install. Which doesnt sound totally bad, but I cannot change it out for him in a decent amount of time. Thanks!!! If it was a manual trtanny it would be easier for me to help with

abecedarian

I can only relate a 'similar' experience with my 91:
Left San Francisco for home and after about 100 miles noticed lots of whitish smoke coming from the truck. Pulled over and found the underside of the truck basically covered with ATF. Checked the ATF level and it was fine so let things cool down then drove the rest of the way home keeping the truck at or below 70 and no more smoke was released even after climbing the Grapevine (I-5). From that time until recently when the engine decided to axe itself the trans didn't give any other sign of problem. So I have to chock it up to it being overfilled when I had it serviced in SFO a month or so prior and the fluid expansion forced it out the fill tube. We never got a warning light about temps, just lots of smoke, and it has not recurred during the nearly 3 years since.

Worse thing that can happen is you change the filter and fluid and drive it and the problem comes back signalling there really is a problem with the trans... or otherwise nothing happens and it lasts a while longer.

And I thought 4th gear was overdrive (which would be the lockup in the torque converter, meaning 3 speed trans with lockup converter)?

DanStew

That is exactly what happened to him. HHMMM

abecedarian

I swear I'm not your friend and this is not my truck you're talking about.

well... it's not my truck you're talking about.

So...?

If he had the transmission serviced at a 'lube' shop, chances are they didn't take in to consideration the expansion (which is why you're supposed to check ATF level with the fluid hot) and filled it with cold fluid to the hot mark. Make sense?
So now I'll defer to my other post saying what is the worst thing that can happen?... it's burned and need fixed... or it was overfilled and just decided to 'burp' the extra fluid out, laying out a smokescreen in the process.
Hope for the best, but expect the worst.

GSGALLANT

Overdrive and torque converter lockup are two different things. Overdrive is the last gear (so... fourth gear in a four speed transmission.) By definition, the gear ratio for overdrive would be less than 1 (In many Toyota transmissions, 3rd gear ratio is 1 in a four speed transmission). Typical gear ratio for overdrive would be somewhere around 0.7 to 0.75, so in O/D, the tranny output shaft is turning faster than the tranny input shaft (tranny input shaft rpm = engine rpm - some slippage in the torque converter).

Torque converter lockup does just what it sounds like... it locks the torque converter pump to the torque converter turbine, which eliminates any slippage and improves efficiency.

DanStew

Talked to my Buddy. Looks like things are going to work out good for him. The mechanic called him and from what i heard (cell phone dieing on him) the mechanic said some linkage got buggered up or something like that, but he is going to repalce that and drain and change filters and he is going to pick it up. My friend did indicate that he was going up and down some large hills so when he gets back I will work with him to get a second oil cooler for the tranny installed. So i beleive we have kept another Toyota from being sold

moegaz

He should just do a tranny swap...

abecedarian

alternately, an external cooler, bypassing the radiator may be more help than the internal rad cooler.