i read the common problems with the injection pumps and stuff but anything i should look for with like engine wise to look out not to buy or transmissions wise? i heard about like #53 cases cracking on tranny? any others i should look for when buying a used 12 valve? thanks.

 

is it a 98 12 valve or 24 valve?

 

it is a 12 valve

 

#53 is the block and i havent heard of any issues with the 12v, just the 24v.
i think the biggest issue is the killer dowel pin, do a search on it for more info. other than that the 5th gear nut usually ends up coming off in a nv4500 manual. not too bad of a fix though.

 

I've had two 53 block'd 12v trucks and wouldn't worry about one... I've heard of ONE 12v w/ a cracked block vs. hundreds of 24v's. I'm sure there are more, but I'm just saying what I've personally heard

the 5th gear isn't a biggie...

what I always advise to people who are looking at a used 12v is to hop in it and get it out on the highway and just stand on it... run the thing as hard and fast as you can for as long as you can. It may feel slow, but as long as everything sounds good and the truck isn't wandering all over the road, that's one of the main issues...

then, pull into a parking lot that's nice and clean and dry and park the thing, hop out and walk around it a drop or two of oil from the breather tube isn't a huge deal, but make sure it's not coating the underside and tailgate of the truck w/ blow-by oil splatter.

look at the road draft tube and make sure it's not just chugging fumes out of it.

if a truck runs smooth, drives well, and doesn't have a lot of blowby, I don't care how many miles are on it or how slow it feels... as long as the engine is good and tight and the steering and brakes are tight, I can fix the slow part