I got stuck in the sand in my 92 w 250, hubs locked 4x low. Lot of revving of the engine but no movement. Tire pressure had been lowered. The tires didn't spin at all, I just sat there. A small 4x came to the rescue with a strap. He gave me a tub and thats all it took to get me going. Back home I had the tranmission
& torque converter checked, they said not the problem. Lack of engine power they say. The mechanic says no that can be. I'm still chasing the MPG's and less power after the injector pump was rebuilt. So I'm not sure what to think.
I have a 93 d250 also so I did a test in the driveway. 2x4 in front of the wheels, both no problem going over them. 4x6 93 no problem, 92 couldn't get over it.
Any ideas?

 

It would have to be extremely under powered to not have enough power in low range to not at least make the tires slip some. My guess is something is slipping in the transmission.

 

At first I was thinking maybe the transfer had slipped into neutral but if it can't drive over a 4x6 then something is definitely slipping. I can walk over a street curb in two wheel drive - but its always at an angle.

No tach?

 

If the motor was revving but the power was not getting to the ground, I am assuming it is not an over powered motor, but more likely a slipping transmission issue.

Over powering a Cummins motor would be hard to do with just sand.

 

Especially in low 1st gear.

 

Did you try it in reverse? When my 518 went, all I had left was reverse.
It does sound like a transmission problem. Even if you weren't producing much boost, a Cummins is still a force to be reckoned with.

 

The first thing I did was have it checked out at my trusted tranmission shop. They say they're not the problem, low engine power. Yes it is a little less than my 93 d250 up the hill. And I did the 2x & 4x test in the driveway foward and reverse.
I thought it was the torque converter trans guys say no.

 

A test in the driveway won't cause enough resistance to tell you anything unless it is slipping really bad. Could be torque converter ,bands or clutches.
something in the transmission is not right I doubt transfer case problems unless it is the shift linkage or coupler between the transfer case and transmission.

 

I agree with the others....tranny problems. My Ramcharger has a bad tranny and can barely get over a speed bump if I nose up to it in 2wd, but I put it in 4low and it does just fine.

 

I'll try the 4x test that way. Would have thought the transmission guys would have recognize that when they had the truck.

 

Maybe not if they treat the symptoms like a two wheel drive driven on flat ground. Hard to say.

 

If you were to chain it to a big tree and then take up the slack then floor it shouldn't you be able to smoke the tires? I'm not saying to try this but if you did...

Or you could put it on a dyno.

 

If the stator is seized in the torque converter than it just becomes a fluid coupling with no torque multiplication. Symptoms would be low power off idle from a stop. The truck should be OK at highway speeds though.

Transmission guys often don't think about this as it's not a slipping condition. The engine would be slow to respond to throttle application.

Try power braking it and see if the RPM's are lower than the other truck. You don't need a tach you'll be able to tell by the sound.

 

Is it possible for the stator to sometime seize and sometimes not. Tried the power braking, they're about the same.
Did another driveway test with the 4x6, 4x4 low no problem, 4x4 high no problem, now in just drive & no problem this time.

 

Maybe the transfer case wasn't engaged. weird things sometimes happen that later on we never figure out.