I own a 92 cummins ext cab le with a518 tranny, turned fuel screw max, maxed out afc star-wheel, rotated fuel pin 90 degrees, and turned smoke screw till it does a lil black haze on start up. I was going up a hill and my temp was at 1/3 and I lost power to the wheels. Hit the gas it just revved. Put in park waited 1 min and still nothing so I shut it off. And i popped the hood i had tranny fluid coming out the top of the spout when u fill it up top. It was all bubbly. So Waited till it was completely cooled down. And gained power and just turned and went back down the hill and home. It's only done this twice both on a paved road up the side of a mtn. I was in 4wd in high. So why does it do this?

 

I have been told that these transmissions do not circulate oil in part they need to be in neutral. It sounds like you ran out of transmission fluid. You might see if you can find someone else with the same truck and compare dipsticks. Also never checked your transmission in part always in neutral for the same reason as above. You might also check your transmission temperature. If you're pulling hard enough to need four-wheel high on paved ground you most probably need more transmission cooling. Just my thoughts most probably worth what you paid for them, Mike.

 

Yeaive read you have to put them in nutreul and I do that. Shod done it there. It was up a mtn so most of it was on dirt with trailer behind me at all. So if if it the tranny overheated do they have like a safety mechanism that causes them to not let you plant power to the wheels?

 

The only saftey for trans temp is that it will kick out of od.

 

So why do you think I lost power on a dirt road on the side of a mtn after engine temp reache a lil over 1/3 being in 4wd?

 

I had a similar experience when I rebuilt a 727 for a friend with a '90. When I re-installed the trans I blew the cooler lines out as usual, noticed flow through the cooler seemed low (not terrible) but buttoned it up anyway. The trans worked great but had a small leak at the dipstick. The next time he drove it, he had to add fluid but worked fine for about 5 miles then quit pulling completely. Let it cool off and it worked fine till it got warm again. It had a whine like the pump was starving for fluid when it would not pull. I dropped the pan and it was full of brown junk. Re-cleaned pan and valvebody and installed a new filter. Trans worked great again. Seems as though filter was stopping up starving the pump. I don't know if he added trashy fluid or if cooler released the junk but it was dirtier than when I tore it down!

Anyway, you may check the filter.

 

When TFs puke out the stick, typically its because they are low on fluid, the fluid gets aerated and foams up real bad, get enough air in the fluid, and it will quit pulling til it settles. Very bad for the trans btw.

 

Ok. Sounds like I better change fluid and filter and see how she runs. Thanks