[mosesburb]

Originally Posted by LOW DOUGH

Originally Posted by justcuz

I used to see that on a lot of early F-250's. The front driveshaft would be slowly rotating driving down the road...at a speed that was not directly related to wheel speed. Yeah, the old High-Boys with the six foot long front shaft. There is only one guess I have on this happening and that is the circulation of oil in the transfer case has a parasitic effect on the front output gear and spins it slowly. The oil is the wind and the front output gear is the blade of the windmill. If you had a clunk hitting bumps I would have guessed slip yoke right away. Nope, no noise whatsoever I found out about greasing output splines on slip yoke when I had that clunking on the Blazer. Transmission shop guy clued me in to it. The High Angle Driveline that I got was completely packed with grease, but the front shaft I had lengthened by my driveline guy was returned dry. I thought filling the zerk would do it--wrong (obviously). I wish I would have known that it wouldn't work prior as it took a bazillion pumps to fill the void in the end of the yoke.

I am slowly learning a little about diesels, when you leave the black signature when you accelerate does that mean you can up you turbo boost pressure a little, or is the black just momentary? Yeah, boost can be added. What the smoke is is too much fuel. Mine is not bad. It pumps a bit out under heavy acceleration at low speed, but is almost non-existent on the freeway under heavy throttle. Excessive fuel in a diesel nets high exhaust gas temperatures (EGT) which will kill a motor quick if allowed to get out of hand. The Cummins from my research seems to be the most cost effective diesel from a reliability and ease of modification standpoint for light duty trucks. They are plentiful because they came in Dodges and the motor will typically outlast several Dodge bodies, so they are plentiful in classifieds and wrecking yards. They also have tremendous aftermarket support which makes modifications simple. Their factory parts availability is good also as these motors came in damn near everything--big trucks (Freightliner, Peterbilt, International), farm equipment (Ford, Case IH, etc), Indutrial equipment (the "B" series Cummins was developed for Case equipment). All of this makes parts readily available at many different locations. Seems like you made a good engine choice. I hope so as I really don't want to re-do it.

Its amazing how just a roughly 10% reduction in engine speed can make such a difference in the way the truck runs. Basically if you ran 35 inch tires the 4.10 would have been fine then. Reason I ask is I am thinking of building a diesel off roader in the future and plan on roughly 35 inch tires with a 4" lift and some fender trimming. Its gonna be a square body Suburban or longbed pickup with a shell.

If you would have told me about the difference I would experience from a slight gear change I probably would not have believed it.