TBosS

I swapped a 2nd gen axle into my front end. My rear is about 10 inches narrower than the front now. I was wondering if you could use the 4.5" or 5" front axle dually conversion spacers on the rear to push them out inline with the front axle? Any thoughts? Has anyone done this before? What issues are we going to see here? Thanks for your input!

u2slow

Spacers that big with standard wheels will load the bearings badly.

Find a wider diff. 2ndgens fit without too much hassle.

Dan s

Just curious. Are you sure you have a dually front axle. With that much difference in width it sounds like u have a Dana 60 from a 3/4 ton.

AZ2A

the OP wasn't saying he had a dually front axle, the 2nd gen axle is 3" wider than 1st gen he is now running a narrower rear axle than front axle and was thinking that if he added dually spacers to the rear axle it would equalize them but it won't it will create a substantial preload on the axle bearings and it gets worse the bigger the tires get... how its 10" wider is strange though unless it is a dually front axle which from the post does not sound like it... why would ya put a dually front axle on a SRW rig and not remove the bud spacers? ok my head hurts now

right now your pretty much running the setup GM put in the first gen Chevy Blazer and GMC Jimmy except those were only 1" wider per side your 2nd gen is 1.5" wider per side... GM did it to make turning more stable for the short lil "Station wagons" (which is how the state of Arizona describes all of my 69-72 Blazers)

Dan s

ok. So the rear end is 10 inches narrower that the front. If he used a 3/4 ton front end the axle tubes would be longer than a 1 ton front end is. Plz correct me if I am wrong. The dually front end is configured so that a rear wheel can be used on the front. That is the only way I could see a 10 inch difference in width. Maybe I’m confused. Lol

Dan s

I just read it again. I’m confused

AZ2A

me too!

u2slow

Rear axle widths
-1stgen SRW 65"
-2ndgen SRW 70" (early) 71" (late)
- DRW pickup 72" (1st or 2ndgen)

TBosS

Yes, there are no spacers on the front axle. It may be closer to 6" than 10. I was hoping to keep the first gen rear because it's powder-coated and fully rebuilt and installed, but I don't like the look of the offset some Chevys have... I was hoping to space the rear to match the front, or at least within an inch. Do the guts of the first gen rear swap into the second gen fairly easily? This is getting out of my zone of experience!

u2slow

You could run the Dodge 6" backspaced wheels on the front, and some 'normal' 4" backspace on the rear. That eats up 4" overall.

The 1stgen D70 r&p and carrier (if 32 spline) can be swapped into the 2ndgen D70 diff. But otherwise everything else is different.

The stock narrow 32 spline D70U with tiny 1/2" studs and backmounted drums really is a bottom-of-the-barrel D70.

TBosS

So I found a 2nd gen rear from a buddy. I can swap in my ring and pinion and the carrier assembly with my limited-slip in it... I'll need to use the axle shafts from that axle. Do the spring mounts need to be moved? How about the tube diameter on the housing? Is that the same size as the 1st gen?

u2slow

Same tube size. Perches spaced the same.

Perches are 3" wide and may need a little grind.