Lift on composite leaf springs?

[HvyChvy334]

Has anyone with composite leaf springs lifted the truck? If so, what did you use/do? My understanding is no one has a kit for this and the u bolts are rounded so you can’t use just any block and u bolt from a kit like Zone, BDS, RC, etc. Any experience or thoughts would be greatly appreciated!

[GETGONE]

GM sells replacement leaf springs if you are adding the GM 2" lift kit to a truck with the composite leafs. I don't know of any aftermarket companies making replacement leaf springs. It would probably be most cost effective to get some from a junk yard that specializes in late model vehicles.

[AJMBLAZER]

Several people have done it on here. Myself included. I put a set of GM 2” lift blocks on and then got some U bolts made because the TB U bolts weren’t long enough. 
 

So far no issues. 

[HvyChvy334]

9 hours ago, AJMBLAZER said:

Several people have done it on here. Myself included. I put a set of GM 2” lift blocks on and then got some U bolts made because the TB U bolts weren’t long enough. 
 

So far no issues. 

Awesome. Do you know what size U bolts you had to get? I know they’re rounded U bolts. Thank you for the info.

[richard wysong]

NAPA has a good selection or if theres a spring shop near you they can make them. get them longer than you need with long threads and cut them or do the math and get what you need

[AJMBLAZER]

I'll look later when I get home.  The problem I ran into was the TB/AT4 U-bolts were made to work with the TB/AT4 rear springs which are thinner than the leaf spring packs that have the composite spring in them.  So when I put the 2" block under the composite spring pack the TB U-bolts were JUST too small.  Another 1/4" to 1/2" and I could have safely threaded them on.

 

I bought some springs online from a place that made them to order and they worked great.

 

They are square U bolts.  The bolts go over the top of the leaf springs, down each side of the pack, and mount to the U bolt plate below the axle so they have to be square.

Edited October 2, 2022 by AJMBLAZER

[AJMBLAZER]

1 minute ago, richard wysong said:

NAPA has a good selection or if theres a spring shop near you they can make them. get them longer than you need with long threads and cut them or do the math and get what you need

This may be true if you have a good NAPA.  The NAPA where I live was unable to locate a U bolt of the correct length, diameter, and spacing.  However I got the feeling after wasting a half an hour on the phone with them that they weren't really able to accurately use their system.  I think the person was just clicking on U bolts and looking at the description.

 

The prices they kept quoting me weren't that great either.

[richard wysong]

Yeah I have a great store, they still have paper catalogs as well as the computer which is sometimes the only way to find what you need when it's not a stock part

[AJMBLAZER]

5 hours ago, HvyChvy334 said:

Awesome. Do you know what size U bolts you had to get? I know they’re rounded U bolts. Thank you for the info.

I bought these:

https://store.uboltsdirect.com/1/2-u-bolts/square/12-x-2-12-inside-width
10.5” long legs. 

Fit great and lots beefier than the parts store crap I tried to use. Stripped out while tightening. 
 

[HvyChvy334]

13 hours ago, AJMBLAZER said:

I bought these:

https://store.uboltsdirect.com/1/2-u-bolts/square/12-x-2-12-inside-width
10.5” long legs. 

Fit great and lots beefier than the parts store crap I tried to use. Stripped out while tightening. 
 

Ahhhh I thought they had to be round U bolts because it’s that way on the bracket that sits on top of the composite spring. Did you have to remove that bracket? Do you have a pic of your current spring setup? Dang composite springs got me all messed up haha. I really appreciate your help!

[Gangly]

I have the composite leaf springs and put a 2" lift on the truck.  I purchased 1.5" rear blocks from Rough Country, along with their extended U-bolts, and everything bolted up nicely.  75k Miles and everything is still buttoned up perfectly with no issues.

[pokismoki]

what's to be gained from composite vs spring steel?

[newdude]

32 minutes ago, pokismoki said:

what's to be gained from composite vs spring steel?

 

 

Weight reduction.  12lbs less per side, total of 24lbs weight reduction.  That I know of and have seen in the field, Silverado LT with the 5.3 are about the only trucks that come with it as LT 5.3.  

 

GM also now has a composite mono leaf that has been making its appearance on the 2022 refresh and 2023 trucks.  

[AJMBLAZER]

1 hour ago, HvyChvy334 said:

Ahhhh I thought they had to be round U bolts because it’s that way on the bracket that sits on top of the composite spring. Did you have to remove that bracket? Do you have a pic of your current spring setup? Dang composite springs got me all messed up haha. I really appreciate your help!

That’s the bracket on mine. No need for a rounded U bolt here. 
 

 

(Yes, the block’s apparently shifted some. It’s still tight though.)

[HvyChvy334]

57 minutes ago, newdude said:

 

 

Weight reduction.  12lbs less per side, total of 24lbs weight reduction.  That I know of and have seen in the field, Silverado LT with the 5.3 are about the only trucks that come with it as LT 5.3.  

 

GM also now has a composite mono leaf that has been making its appearance on the 2022 refresh and 2023 trucks.  

Yeah apparently my 22 has the mono leaf which is throwing me off a little. I’m not sure how different it is than the pre-refresh other than a single leaf.