I´m having gearbox problems with my 1996 Explorer.
When starting up it takes about 20 sec. before the car moves, thereafter running ok in all gears high ad low.
But there are no oil pressure to the cooler, and the oil gets hot within aprox. 10km of driving .
What can be the problem ??

 

You just know I'm going to ask this question, when was the trans last serviced fluid and filter ?

 

Yes off course - New filter and new oil is on !

 

Does that mean it is on the to do list or has been done recently ?

 

I have bought another `should be ok gearbox`, but it is not working at all - no gears and no oil pressure - so I am stuck for now.

 

Please be as specific as you can.
Need to know exactly what you did with your original trans AND did you open up the replacement? If so, what did you do with that trans.

I have a suspicion , but no need to go into it if not called for, OK ?

 

The original trans suddenly began only to drive in 2nd or 3rd low gear (not sure which). No shifting to other gears or high level was possible.
The 2nd box had a smell of burned oil. Oil and filter was new but the symptoms as first described .

 

Just to cover the bases,
there are 2 tangs on the torque converter that MUST index with the front pump gear or the converter can fracture that gear resulting in no pressure..
Did you have any problem bolting up the replacement trans ?
NEXT,,,,,,,Any trans that has burnt fluid has been overheated from internal slipping, therefore a BAD trans. It is no fun being the bearer of bad news, but that trans has to come back out.
.
Will the place that sold you the bad trans,exchange it for a really good one ? Be careful, they are not the one doing all the work.

 

By the way : can lack of oil pressure to the oilcooler have other issues than the front oil pump ?

 

The pressure the front pump develops gets divided between what is called line pressure and some is circulated thru the oil cooler..
There are pressure taps to check the various pressures. Bushings , and sealing "O" rings keep that pressure from dropping too low as also does a pressure regulating valve..
When costs are a determining factor, like always, a shop rebuild could be a solution. Some shops will reuse old parts that pass measurement checks.
That line pressure gets directed to all controls and components.. Guessing can get expensive, might consider having a trans shop do a thorough diagnosis.
There are trans control modules that also get into the pix.