Will a 2.5" rear block/ubolt app for 73-91 work for a 71?
 

So I have had rear Rough Country 2" blocks on order through Jc Whitney for over a month, and now they are telling me it will take 60+ days to deliver.

I called Rough Country, and they have plenty in inventory! They are not allocating any to JC Whitney for whatever reason, and the rep was being a d$ck.

So, strike 1 and 2 against JCW and RC.

I called Explorer Pro Comp, and they have a 2.5" block/ubolt kit for 73-91 Blazers, but neither one of us could figure out why it wouldn't work on a 71... Maybe leaf spring thickness?

Any ideas?

As far as I know, the only difference between the springs in the later years is the length. Also, the perches are in a different location on the axel, but other than that, I thought they were basically the same. Ya might post this question in the garage on CK5.com or on Pirate4x4.com. Also try calling a 4x4 shop. The manufacture probably can't recommend putting it on a vehicle that it isn't spec'd for, but the shops would probably know if it will work and would be more willing to tell you (especially if you make it sound like you might have them install it.)

i had a 4" lift on my 90 blazer and took it off and put it on my 72. it is an all spring kit from rough country. the U bolts worked fine. yeah i did have to relocate my front spring hangers.