Posted by Will Liebscher on Wednesday, July 02, 2003 at 2:21AM :
In Reply to: Re: Question about Tall Tires? posted by RDavis on Wednesday, July 02, 2003 at 1:00AM :
Davis, I'm not very versed in the WDX-WM300 PW's. I think they are similar to the M37's in their drivelines. I don't know how tough the NP420 is, and I have asked several times, what is the torque rating of this trans, and when was it designed? (I hope you're not referring to the SM 420, I confuse them sometimes myself!) What is the dia of the Input and Main shafts?
What is wrong with the NV4500HD trans? Are you running one now? Behind what engine?
The father of the NV series and NV itself, is New Process, and the NP 540 series trans (541 & 542). They are from the '60's and 70's era. Pretty difficult to find now in OD, and only 20% at that, but they have a huge range of ratio choices, Cast Iron Case, 2 PTO covers, easy to work on, and they will carry at least 550 ft lbs of torque. I run one, and own several. I like them behind my Chevys. (But I can't wait to try an NV w 28% OD.) When we split these 540's with a planetary over-underdrive, and a 1.5 to 1 Transfer Case (NP 200), we get 28 distinct fwd. gears, and 4 reverses. Pick your gear, and pick your Hill! Thanx Will Liebscher
PS And there is a subtle difference between changing gear ratios thru a change of ring and pinion, and thru changing tire diameter. John Rix has done all this together in his M37 which is powered by a 453 Detroit, Blown and turbocharged. We have found all(?) the "stress points" in the driveline, (ie broken everything), and enhanced most of them to a reasonable plateau beyond stock. It can be a vicious circle or it can all be done. Thanx Will Liebscher
Follow Ups: