Spring perch in front axle

[millerofmadison]

We're rebuilding my son's 87 Blazer after a wreck pushed back the front axle several inches. Got the leaf springs off and need to get a new tie bolt/nut to hold the springs together and secure them between the axle and anchor plate.

There were no spacers between the plate/leafs or the leafs/axle. In looking at LMC, it looks like there should be some there. Should I add the spacers?

Also, when I install tie bolt does it go in upside down (nut on top of leaf springs, under anchor plate)?

Finally, u-bolts were bent just a hair when I took them off. Should I go ahead and replace them?

Previous owner did a lot of stupid stuff (often left off a number of crucial parts), so often it does no good to look at the other side to see how it should be done!

 

[dremu]

I believe the bolt you're talking about is called the center pin. You can get specially made ones, or make your own with an appropriate-length 3/8" fine-thread grade 8 bolt. The "real" ones have round heads; when doing it yourself you can round the head off with a grinder. I use the "poor man's lathe", i.e. chuck the bolt up in the drill, then run it with the head against the bench grinder. Regardless, make sure the nut is TIGHT (vise grips on the round head and tighten the nut) as a loose center pin can allow your spring pack to separate, resulting in catastrophe. If you have a torque wrench, the spec for 3/8-24 gr8 is 48-50ft-lbs dry.

The round head goes DOWN into the spring perch and the nut goes up top. The nut shouldn't fit in the perch -- if it does, you're in trouble

I believe the spacers inbetween the leaves are plastic anti-squeak gizmos. If you're doing a lift or other modifications you'll sometimes see spacers between the spring pack and the axle ("zero rate", "EZ inch"). You may also have angled shims there to correct suspension geometry, but for stock suspension you would not likely need any of these.

U-bolts are torque-to-yield, i.e. will deform during installation, so they are one-time use. You will want to replace all of them in your situation since yours have experienced more stress than they should (i.e. the wreck.) Read up on the tightening process, and remember to re-check them at, say, 100 and 200 miles once the truck is driving. Torque spec for U-bolts will vary by size, Google it or check your service manual.

Oh, and welcome to CK5, and welcome to Fixing Stupid Crap The PO Did 101. The only thing worse is the next class, Fixing Stupid Stuff You Did To Your Own Truck. Been there, done that.

-- A

 

[sweetk30]

x2 on his post .

and welcome . here we have what ya need info wise and no b/s like other sites.

 

[millerofmadison]

Thanks for the help. We've seen a lot of stupid things so far--worst has been the rear axle that had no brakes on one side--nothing but wheel cylinder--not even a drum!

 

[dremu]

Thanks for the help. We've seen a lot of stupid things so far--worst has been the rear axle that had no brakes on one side--nothing but wheel cylinder--not even a drum!

That's actually the rare factory option for three wheel drive

You've then noticed first-hand that most of your braking comes from the fronts.

Still, wow.

-- A

 

[454Sub]

I took mine apart once and only had 2 flexplate bolts in, and one nut holding the torque converter to the flexplate.

 

[Avery4jc]

Just get an allen bolt for the center pin. It's a higher grade and the head doesn't require any work to fit in the spring perch hole.