conversion to 98 12 valve

[CSnyder]

just bought a cherry 89 reg cab 3500 with single rear wheels with a 360/ 4 speed 4x4... now i want to know what the biggest obstacles are to convert this to a 98 12 valve i have laying around... any suggestions or am i biting off more than I can chew?

 

[JApplegate]

just make sure the power train can handle that Cummins!!

 

[bgilbert]

Make sure you use a diesel transmission, diesel rearend. Sell that 360, gasser transmission, gasser rearend, the t-case might work depending on if you use a diesel auto or stick. Sounds like a sweet setup you will have. You do have a 5600 and Dana 80 to go with it don't ya?

 

[CSnyder]

haven't got the diff's or transmission or transfer so maybe I'll just keep it a gasser and throw in a big block with straight pipes... keep the kids with their 350 gassers in check.

 

[Joseph Donnelly]

The diffs are probably OK, but may need bigger companion flanges for bigger u-joints, and bigger driveshafts. If the t-case is the NP 205 iron unit, it is fine; if the aluminum NP208, not strong enough. Get a diesel transmission for sure; one way is a built up complete NV4500 from std. trans. You will need first gen motor mounts and brackets (I have a set of the brackets if you need them).



Clearance to the power brake booster and master cylinder is fairly tight, but workable. Contain that KDP while the engine is out, and remove, spray clean, loctite the mounting bolts inside the case. Check the front and rear seals; might as well replace the front one when you take off the gear case cover.