Hi all,
Took my new to me 2000 dodge ram van on a drive today. Seems like after 10-20 miles at highway speed the O/D turns off and shortly thereafter (even after dropping speed to 45) the transmission temp light comes on. Supposedly, this is a new rebuilt tranny. Any ideas?
Edit: I just checked the fluid. After parking for 30(?) minutes, I went back out, started it up, let it run for a few minutes (3-5), put it in neutral and checked it several times. It was definitely above the max line but not past the wavy part of the dip stick... maybe I'll grab a picture to demonstrate.
Could that really cause this issue?
Edit: Checked again after cycling through gears - down to 1, then 2, then D, then N. Not sure if it was that or if I was imagining it, but it appears to be filled right to the max. Not over.
Sounds exactly like this... I'm not sure if I'm buying the solution of reflashing the computer: transmission O/D off trans temp light | Tech Support Forum

 

Does yours have the check valve in the trans cooler line? If it does, remove it. See if the problem goes away.

Something else to check, was your trans for a 2000 or newer? Trans temp sensor changed in 00.... and it shows by the trans getting hot WAY faster than you think it should.

 

Where do you guys get detailed drawings? I bought a Haynes manual, but it is not especially illustrative.
Otherwise, I'm not sure how to check for a check valve other than tracing lines and looking for a wart of some sort.
Oh, and to your question about the transmission, I'm not sure. The previous owner had it rebuilt.
Thanks,

 

Browsing google, it looks like this is the right part and it looks like that brass-looking part is a check-valve. I watched a video on deleting the check valve from the line, but it looks like it's as much work as replacing the line and at $40 for the new line, it'll probably cost me at least half as much just to make sur eI have the right hoses, clamps, and such.

Any magic tricks to keep the new trans fluid from running out if I replace this whole line.
Maybe the best bet is to drain it from the pan and then re-use oil since it's new?
Dorman Transmission Cooler Line Assembly 624-816 (autozone.com)

 

Don't need to replace the line at all. That brass feller is indeed the check valve. Remove that section of line from the van, drill out the check ball in the valve, clean the line out really well, reinstall. Done. Little or no cost.

Need the cool little tool to release the quick connect at the radiator though, I think I paid less than 10 bucks from one at Advance Auto. (3/8ths I do believe.)

 

Thanks for the advice!

I read that it was good to keep the valve so the transmission gets to operating temp faster. Not true?

To drill it out and flush it, you’d have to take the whole line off, right?

 

The valve tends to clog, and PREVENT flow. So, yeah, the trans gets hot faster... but, it won't cool either. The real purpose of the check valve is to prevent converter drain-back. With the valve gone, on cold starts, there will be a few second delay between when you put it in gear, and when it actually starts moving, as the pump needs to refill the torque converter. Has to sit for a while for that to be an issue. (the pump does not charge the converter in park, that's why you check fluid level in neutral.) It is a very minor inconvenience, and once you get used to it, it simply doesn't matter. I just start the truck, put it in whatever gear I am going to need, fasten my seatbelt, light my smoke, and it's ready to go.