Dana 60 swap - 4" front springs - Shims?

[sw99]

Getting ready to swap in the front 60 into the Blazer (1990) and I have a question about whether or not I'll need some degree shims with my particular set up. I had a K30 before with a similar lift and had to use 2* ones to keep it from binding.

I'll be sticking to 4" on the lift height to keep the low center or gravity. Tires will more than likely be 37's with fender trimming. Can anyone tell me if I'll need to run shims on this as well? Trying to get all the parts so I don't have too much down time. I did buy a PartsMike .250 yoke that is supposed to help with interference.

Thanks!

 

[K85 Octane]

You wont have any binding to worry about, not with just 4". Just make sure the caster angle is correct. IIRC 6-10* but I'm at ~7 I think, never really double checked my measurements after putting it all together lol. Drives perfect I pushed my axle 1.5 forward with zero rates. Had ORD cut a 4 or 5* angle in the zero rates, can't remember.

basically I'm just ranting and letting you know just be ready to buy whatever you need, that included an angle finder, I like my digital cube from OSH, did the alignment with it too, free bump

 

[sw99]

Yea not moving the axle forward yet, stock mounts for now. Just the 4" springs and some HD shackle (Same height dimensions). I bought some 2* ones just in case. Anyone know if I'll need them with my set up?

1990 Blazer (350/700R4/NP241) with 4" lift front springs and stock height shackles?

Thanks folks!

 

[1-ton]

With 4" lift you should not need your wedges. Your drive shaft angles will increase a little, but not by enough to matter (2 to 3 degrees at most). When it comes to a trade off between positive caster and increased drive shaft angle, it is better to choose more positive caster (especially with larger tires) over a slight increase in drive shaft angle. Besides, there are ways to deal with small increases in drive shaft angles, such as an off set u-joint at the diiff side, and a little grinding to the double cardan joint at the transfer case side.

With one of my trucks (10" lift) I had a lot of drive shaft angle increase, and with out the use of any wedges, I used an off set u-joint on the diff side, grinding on the cardan joint (transfer case side), and a spacer to lengthen the shaft, which made the increase livable as long as I do not go more than 40-MPH while in 4-HI.

 

[Kay86K5]

You will be fine. I had that exact setup on my k5 before going 52's in the front (4" lift springs front, d60 with stock shackles) and never had to worry about shims. My brother has the same thing too with no problems whatsoever, you will be fine. Just throw it in and take some pics

 

[sw99]

Well I have everything I need for the swap, at least I hope so. I bought three 2* shims just in case I need them. I know GM used a .5" longer front shackle in the later model Blazer so I guess I'll wait to cut my center pins just in case I need to adjust caster. Now I just need to find the time to get moving on this pig...

I also need to see where I'll be at with the rear. I'll be doing the 56" springs so I may have to go with an old flat overload spring to level it out.