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PaulS
04-20-2001, 12:46 PM
What would you expect to be the symptoms of an overheated automatic transmission on a '96 4x4? (Hot day, highway driving with occasional stops)

I don't want to describe just yet what I experienced a couple of years ago--I'd like to see what you say without knowing what did happen. After thoroughly hosing the radiators (one of which is the transmission fluid cooler) the problem never returned, so I presume my layman's diagnosis was accurate. There was a hole lot of dirt and dead bugs in there! I now clean the rads every summer. (Before that, I hadn't realized just how many different radiators the truck had behind the grill!)

Garet
04-20-2001, 02:45 PM
Hard shifts, fluid discoloration. Strong Odor of buring tranny fluid. If the dipsitck has a varnish coating on it this might be an indicator. All this was from my troubleshooting book on automatic trannies. The causes are low fluid level, fluid cooler lines clogged, clogged oil filter or screen, internal fluid leakage, or in your case the cooler was plugged with debris. Usually though the tranny will not overheat even with a cooler plugged since a lot of vehicles don't even need them unless towing is involved.

Garet

PaulS
04-23-2001, 12:48 PM
The only symptom of those was the hard shifts. No towing was involved, either. Everything was fine in top gear; the problem was getting up through the lower gears... It really didn't want to shift up. (It would rev high, and I'd feel it try to shift, and fail, until eventually it would go to the next gear.) The first thing I did was check the tranny fluid. It was at a good level, still nice and clean, bright red.

That was almost two years ago and the problem has never recurred. Since the only remedial action I took was to clean out the rads, I still think it must have been an overheated tranny.

If there's something else I should check (or have checked), please let me know!

cutter150
04-23-2001, 01:18 PM
i never thought about that, i have a 96 4x4 as well do i have a transmission cooler and where is it at if i have one, i didnt realize they came on the truck stock?

85w/350
04-23-2001, 02:52 PM
Speaking of tranny troubles....
My 82 chevy longbed with a TH350 tranny is hesitant to engage from park when its cold and even sometimes when its warm. Its like once you push the gas enough and the engine reaches a certain RPM it kicks in finally. Can be annoying sitting at a stop sign waiting for it to kick in while you are starting to roll backwards. I changed the filter and fluid(keeping everything super clean) and that stopped the problem for a matter of days. :(
On my other truck my 85 GMC shortbed i never had this problem before same engine and setup...also changed the fluid and filter just because it was about that time. Now its starting to have the same symptoms.
What i think: Either I added too much tranny fluid the local auto parts store told me 4qts? Or miraculously both are going out at once. Like I said I was careful to keep the filter and everything within the tranny clean. Also my 85 is starting to leak fluid since i changed the filter and fluid(another problem i ddint have before). I used the gasket adn all but i didn't use any type of liquid gasket because the local autoparts store said it was not necessary. All bolts are tightened down on the pan.
What do you think?

75
04-23-2001, 07:02 PM
85w/350 - that sounds like the symptoms my T400 was giving me a l-o-n-g time ago (didn't know very much about trucks/cars/etc then) before the transmission finally "went south". Necesito total rebuild! :( My fault - the torque converter was starting to break down, which was causing the slippage - most noticeable when cold, as it got worse when warm as well, and I didn't pay attention to the problem soon enough. NOW I know better!

With regard to the pan leakage, the pan itself may be slightly warped.

Not saying for sure that the torque converter is the problem with yours, but the symptoms appear similar. Best bet - get it checked out soon!