99 Explorer loses all gears when hot

[nameiztaken]

Figured I’d ask here as well since explorers are so similar to rangers.

I have a 99 Explorer Sport with 4.0L, 150k and 5R55-something auto trans. Drives fine for about a mile, then loses all gears until it cools off for a while. Not to keen on replacing the entire transmission if I don’t have to. I know they have issues with servos, as well as valve body gaskets.

ATF is a darker faded red, doesn’t smell exactly burnt. Smells like well used ATF (I have no idea when it was last changed). No check engine or warning lights are illuminated, even during the gear loss.

Even temporary solutions are fine, just enough to use the truck until I can afford a new transmission.

 

[Dirtman]

Stupid questions first. Is the fluid level where it should be?

 

[nameiztaken]

Stupid questions first. Is the fluid level where it should be?

Bought this car same day I posted this thread (paid well below market value, even with a shot trans). Anyway just checked the level while it was warmed up and running in park, it was 2 inches above the max level

I wonder if that says anything... Next step might be to drain some of that fluid and see what happens. Maybe look for metal bits while I’m at it..

 

[Dirtman]

If the fluid is too high it can get way up into the gears themselves and get sloshed around turning into foam... and transmissions cant run on foam...

 

[RangerFabWorks]

Sounds like a weak pump to me.

 

[adsm08]

Bought this car same day I posted this thread (paid well below market value, even with a shot trans). Anyway just checked the level while it was warmed up and running in park, it was 2 inches above the max level

That means the fluid pump is not working. At that mileage I would not do the needed work to replace the pump without doing a full overhaul. You are already 90% of the way into the work for an overhaul just to replace the pump, and you have a transmission that is more than 3/4 of the way through it's life expectancy.

If you let it cold soak overnight and check the fluid BEFORE starting it, again right after starting it, and then a third time after it looses gears you will see it go from overfilled, to correct, and back to overfilled.

 

[nameiztaken]

That means the fluid pump is not working. At that mileage I would not do the needed work to replace the pump without doing a full overhaul. You are already 90% of the way into the work for an overhaul just to replace the pump, and you have a transmission that is more than 3/4 of the way through it's life expectancy.

If you let it cold soak overnight and check the fluid BEFORE starting it, again right after starting it, and then a third time after it looses gears you will see it go from overfilled, to correct, and back to overfilled.

I tried this and its exactly as you described, fluid level changes when it starts slipping and the transmission sounds (literally) like the pump is shot. Started noticing an almost pump cavitation-like noise coming from the transmission when in any forward/reverse gear.

Would rebuilding the entire trans and replacing the pump/torque converter be worth it? what can I expect cost wise if I were to do the rebuild myself? I know the torque converter is on its way out as well (moderate tq whine).

 

[rusty ol ranger]

I tried this and its exactly as you described, fluid level changes when it starts slipping and the transmission sounds (literally) like the pump is shot. Started noticing an almost pump cavitation-like noise coming from the transmission when in any forward/reverse gear.

Would rebuilding the entire trans and replacing the pump/torque converter be worth it? what can I expect cost wise if I were to do the rebuild myself? I know the torque converter is on its way out as well (moderate tq whine).

I would just go pull one from a boneyard.

 

[adsm08]

I tried this and its exactly as you described, fluid level changes when it starts slipping and the transmission sounds (literally) like the pump is shot. Started noticing an almost pump cavitation-like noise coming from the transmission when in any forward/reverse gear.

Would rebuilding the entire trans and replacing the pump/torque converter be worth it? what can I expect cost wise if I were to do the rebuild myself? I know the torque converter is on its way out as well (moderate tq whine).

If you do it yourself, I don't know what the cost would be. I can't even guess because I don't know what hard parts you will find worn or damaged when you get inside.

I just priced Ford reman for my own Explorer, and my price was just under $2700, and that's with me installing it.