72 K5 Blazer Advice

[Munchiezzz]

i got my hands on a nice 72 k5 im wanting to turn into an off road beast. i live in the middle of the desert with great trails and very close to Moab, UT. i want a trail rig that can also rock crawl and conquer Moab but still want to keep it street legal. i need advice on a few parts since pretty much all articles i find are for jeeps (nothing against jeeps)...

what to do for suspension? (best lift kit, how high to go)
what to do for axles? (i was thing D60 for back, D40 for front)
what to do for engine? (probably go crate engine, how big is to big, gm has great engine choices)

 

[woody]

D60 front, D70/Sterling rear. D44 is pathetically weak.

Suspension: as low as you can keep it Obviously depends on needed tire size (Moab is 100% doable on 35's or 37's)

Engine: reliable fuel injection. Overpower it and your axle choices get more expensive.

 

[SteerAndStuff]

Here is my old 71 k5. Had a 454, th400, 203/205, Dana 60 front, 14ff rear, 43s. Was big, heavy, and not spectacular at any one thing. I had 52" rear springs in the front and shackle flip rear, likely 4-5" lift ish. You will definitely want a 60 or equivalent front and would do a late model LS based engine nowadays for sure.

 

[Stockblock]

Offroaddesign.com or diy4x.com will be you go to sites for any and all aftermarket for Jimmy or Blazer parts.

I've got a 79 K5 on ton's that I've run 44" boggers and now 37" pro comps with a 8" lift. I am slowly downsizing it to be more street-able since its glory days as a mud truck.

Keep in mind that these trucks can get heavy (+7,000lbs) once you upgrade to tons, +40" tires and a taller leaf springs. This all leads to stability issues on the rocks which is why you don't see many of them crawling around out there.

IMO, figure out your budget and needs before pulling the trigger on ton's. If you looking to keep this thing street legal/daily driver, then I'd look at Dana 44 front and 14 bolt rear with no more than a 37" DOT tire. Run a 4inch spring + trim your front fenders and enjoy.

 

[Broski]

I don't know Blazer's, But I do know you want the lowest lift & biggest tire you can fit ( today's 37s are 40s ) Dana 60 front and 14 bolt or sterling rear.
Move the front axle forward and do a lot of cutting to make the big tires fit. big lifts to fit big tires is old school.
LS for sure

 

[pennsylvaniaboy]

for suspension, if you want simple, get the tuned springs from ORD. keep it tension shackle. I went thru the whole 48,52,56,63 spring combos, and in the end I would have rather had good, fresh springs from ORD that used nearly stock mounts. Crossover is a must.

For axles, DO a 60/14 bolt.

Engine, at this point I would go 6.0/4l80 from any GMT 800 truck. and put a 205 behind it.

 

[Broski]

If funds permit a 4 speed atlas transfer case would be the Cats meow !!

 

[SteerAndStuff]

Another option would be a later model 6.0/6L80(6l90) that has a 4:1 first gear then a 205 behind that.

 

[pennsylvaniaboy]

^^^^ i dig that idea...