My son's 98 Ram 1500 w/ 3.9 V6 2wd leaked coolant and overheated. Automatic transmission overheat light came on as well. It turned out that the waterpump was bad. Replaced the waterpump and now when we put it in reverse the truck appears to be in neutral. When in neutral it moves forward. I just replaced the transmission with a used transmission with 90,000 miles on it (truck has 315,000) and it worked fine until the truck overheated. Is this change the fluid and filter or is the tranny toast?

Thanks in advance for any help.

Roadrunner02

 

you would be in good shape if u had a toyota always moving forward lol check all your the cooling system cause your transmistion fuild dose flow in to your radatior to get cooled

 

There is a transmission cooler, in front of the rad. The coolant and tranny fluid dont mix lol. How are the levels? Whats the color of the tranny fluid?

 

If I understand correctly the transmission still works correctly except that the indicator is off. It shows neutral but you are in drive? If that is the case, all you have to do is adjust your shift cable. How you got that messed up swapping out a water pump is beyond me.

 

Transmission fluid appears to be down about a quart. I'll check more this evening. Color is good. Would low levels be sufficient reason to keep it from going into reverse?

 

I couldn't think of any connection between the water pump replacement and the transmission. That is why I'm focusing on the overheating.

 

Whether or not you have a factory cooler in front of the radiator , the trans fluid runs through the side of the radiator as well. See the lines going in and out on the passenger side. So when it overheated , the trans fluid overheated as well. Which is obviously not a good thing.