Leaf Spring Question

[chesspirate]

After I put a set of 3 inch lowering blocks on the back of my truck, I had fun getting used to the feeling of leaning back, and the improved handling of the vehicle. One point of concern became apparent though. If I go over a large bump, or hit a larger than normal pothole, I hear a clanking that sounds like the leaf springs are hitting eachother or something. I can't tell what it is. Has anyone had clearance problems with drop blocks? Or has anyone had to replace old, wornout leaf springs? Any thoughts would be appreciated.

[OBI WAN]

Did you use angled shims??? Leafs are not the problem with the noise, that I can say!! Did you check and make sure the driveshaft had the appropriate travel room now that its 3 inches lower and isnt that slamming into the tailend of the tranny?

[firehawkclone]

1.did you retorque the u bolts and spring eye through bolts?
2.do you have the 3rd shock on your truck?(shock above passenger spring)
3.is your truck a zq8(extreme)?
4.how far away are the bump stops?
5.are you hit the bumber on the ground?

i know im missing something easy here!

THANK YOU MASTER

[LayItLowS10]

4.how far away are the bump stops?
THANK YOU MASTER

thats my guess without more info or the truck in fornt of my face

[bvr775]

did you use a mono leaf or multipack leaf?

[chesspirate]

Stock leafs and the truck came as a 1991 extended cab with the towing package. And it's not a clunk like something hitting something its more like a clatter of a couple of things making the same pitched noise in sequences, try this on; if you could brake down the sound of a crunch (c-r-u-n-c-h) but each part sounded the samed (c-c-c-c-c-c) and then played it at a certain tempo, and after each bounce the tempo slowed, so
(ccccc) (c-c-c-c-c) (c--c--c--c--c) done.

The noise is also related to the speed of the bounce, actually, thats why I thought it was the leaf springs.

[firehawkclone]

for some reason it sounds like a u joint!

[bvr775]

I must have missed that......3" blocks........

well i can tell you why your u-joints will go bad, but i can't tell you that's the problem. more likely your U bolts have loosened up or u have cracked a block.

replase the the u-joints. get some angle shims and some leafs and throw the blocks away. shim the the tranny up 1/2" and the carrier crossmember up 1". this will help regain the proper driveline angle.


get some extra u-joints cause your eat them pretty quick with tall blocks like that.

[chesspirate]

these things are practically brand new! Only two weeks old actually and the sound isn't constant, it only happens when the force on the rear end is big, so i don't hear it just cruising down the road, but if I hit a decent sized bump there it is

[chesspirate]

Also, would dropping the front end, say, 2 inches, bring the driveshaft back into realignment? or at least close?

[firehawkclone]

check the bump stops and those u bolts!

droping the front will just make your truck look better,but it won't chang the D/S angle.

let us know what you find!

[bvr775]

Also, would dropping the front end, say, 2 inches, bring the driveshaft back into realignment? or at least close?
no.. the front end will have nothing to do with driveline alignment unless you have a 4x4, but you should definatly lower the front too cause have your nose in the air will screw with the alignnment and sterring geomtry and all that crap.


your going to have to put some shims under the tranny mount and raise the carrier bering to get the driveline lined back up.

someone give him a link to some solid blocks and the fat u-bolts. i thinck there on the v8 conversion site, but i can't find the link.

[Admin]

Here is a good article I found and placed and put into our article section.

http://www.sicgmtrucks.com/forum/article.php?a=165

[Hammer]

speaking from experience, like many others here, i can tell you first hand that if you don't shim the tranny and make sure the blocks are tapered those cheap blocks are going to cost you:

ujoints at the least,
pinion gear
rear seal on the tranny
front seal on the diff case

I strongly advise that for more than 2" you consider mono leafs, they won't alter the clearance between the axle plates and the road and give you a nice ride. you will STILL have to shim the tranny though or get a 1" angled block.

The noise could be the ubolts dragging on the ground every time it bounces, but more likely loose ubolts or hardware, like others have said. these guys know what they are talking about.

In all honesty, i would take the blocks out if you can't get the tranny shimmed or consider the mono leafs. 3" blocks are tall and you can get swaying and all sorts of weird behaviors with blocks.

Good luck, hope this was helpful.

[inprogress10]

the bottom line is anytime you put after market parts on a vehicle you are going to have problems. you are going to have to check more things than you normally would. if you decide to start cutting on it and adding bags or whatever you will have even more maintenance to do. i have drop spindles and blocks on my truck and it rides better than stock but just like you occasionally i will bottom out on a bump.

[LilYellowZQ8]

The noise could be the ubolts dragging on the ground every time it bounces, but more likely loose ubolts or hardware, like others have said.

There is no way his u-bolts can hit the ground when he hits a bump. Heres why. The axle moves independently from the vehicle, so the u-bolts will travel with the axle and leaf springs. But even then, his tires would have to go completely flat in order for that to occur. It sounds like you are bottoming out the driveshaft inside of the tailshaft, binding up the carrier bearing/ or u-joints, or just bottoming out on the bumpstops.

[LayItLowS10]

nail on the head lilyellow, i still think it is bumpstops, are they stock ones, did ya cut em down. but yeah def must look into pinion angles also even if the problem is the bumpstops. buy an inclinometer (angle finder) and measure em. costs only 10-12 bucks and comes in handy alot.

[firehawkclone]

whats the best pinion angle?

[bvr775]

There is no way his u-bolts can hit the ground when he hits a bump. Heres why. The axle moves independently from the vehicle, so the u-bolts will travel with the axle and leaf springs.
well actualy... a 3" block will put the sping mounts really close to the ground then you have the extra tread shaft from the u-bolts sticking out as well. If if didn't cut the X-tra tread off even with the nut like most good aftermarket block kits advise, then that in combination with the tire sidewall size and the compresion of the tire over bumps will cause the the u-bolts to scrape and in most cases come loose.
this is an easy thing to diagnose and fix trough. U'll be able to tell if the u bolts have made contact because they will be bent and/or ate up on the tread shaft ends. retighten or replase the u-bolts and hack off the X-ces tread. If you still have the problem go with taller tires.

[chesspirate]

Okay, so now that I've been berraded for being an idiot, maybee I can throw another question out there.
What would be the best way to lower the vehicle if I had to do it all over again?

[LayItLowS10]

not an idiot man, everyone makes mistakes
how much of a drop you looking to do

[XxInFaxX]

yeah, as layitlow said, not an idiot...and there are no stupid questions...only stupid questions are those gone un asked

[bvr775]

Okay, so now that I've been berraded for being an idiot, maybee I can throw another question out there.
What would be the best way to lower the vehicle if I had to do it all over again?
don't take it like that. We all have to learn some way.
blocks are good way to find out how low or how high you want to go, but they are in no way a permenant solution. these supension dealers never tell anyone the risks of useing tall blocks as a permenate solution. It's bad for sales. you can get solid billet steel blocks, still not a permenate solution, but it's a much better solution than cast hollow blocks. (as soon as I find the link i'll post it)
If like the truck sitting 3" lower you can get leafs from belltech who sells a multipack leaf at a resonable cost or gound force who sells a mono leafs for a bit less. the multipack is better for people who use there trucks for carrying loads. the mono leafs are supposed to give you a better ride. beyond 3" you looking at a 4 link and bags or a coil-over conversion
If your looking for more performance your going to have to call a place like eaton and have the leafs made, but you'll only get a 2 1/2" drop out of most perfomance springs. you can use a 1/2" or 1/4" spacer and a pinion shim to get the full 3".



as for the front. try use as close to factory heigth coils as you can.3" is too much when dealing with an all coil drop though. you can achive a decent drop while retaining most of your factory sterring geometry useing droped spindels in combination 1" belltech, ground force , eibach or 2" zq8, eibach, qa1 coils.

[firehawkclone]

there was no stupid question/s being asked here chesspirate.becuase I think were all more concerned with your safety,so have you found the problem?is it your u-bolt's or something else?The blocks are ok for now,but when you go to do the front i would(and did)get some drop spindals and coil's.

let us know what you have found.

[chesspirate]

Okay, took the truck in to the place where I got the blocks installed and ran through all the questions you guys prompted... They took it into the shop and looked at it, even let me stare at it and talk with them about it... The verdict... Replace the blocks with angled blocks to correct for the rearend hike and put the driveshaft back in alignment. I've been driving it for a couple of days now on some knarley roads no less and the weird noise is gone!!! Also, ride is a smidge smoother so I figure that shows that the driveline is in better alignment.
Also, we looked at the bumpstops, they looked good, almost too good actually. But since my noise went away i'm stoked, let me know what y'all think

[firehawkclone]

Right on dude!

If your bumpstops are real close to the axle,you can allways remove the bracket and install some after market stops.

[chesspirate]

Would there be any advantage to aftermarket stops? I figure I'll be putting lowerd springs on in the not to distant future, so would the bumpstops still be something to consider?

[firehawkclone]

Well with a 3" drop you should be real close to the factory stops,so you can get more suspension travel if you cut/grind off the steel bracket thats welded to the frame and drill a hole in the frame and bolt on some other stops.thats all

[Maxx]

Here is a link for you guys to read. I think this is the one bvr was looking for.
http://www.v8s10.com/Pages/Parts_S10-Driveshaft-Align.html

A question though, who else makes shimmed(angled) blocks?

[Hammer]

There is no way his u-bolts can hit the ground when he hits a bump. Heres why. The axle moves independently from the vehicle, so the u-bolts will travel with the axle and leaf springs. But even then, his tires would have to go completely flat in order for that to occur. It sounds like you are bottoming out the driveshaft inside of the tailshaft, binding up the carrier bearing/ or u-joints, or just bottoming out on the bumpstops.

wow what was i thinking.... lol