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Polyurethane Bushings for Leaf Springs - INCREDIBLE!

25K views 53 replies 25 participants last post by  SportsBoy 
#1 ·
I just upgraded my black rubber leaf spring bushings with red polyurethane ones. I'm totally amazed! The van handles better and feels more solid. But for me that's not the amazing part, I had expected that.

A little back story...

I have a bare bones cargo. No interior luxuries to deaden sound. I hear everything. My van creaks and squeaks like you would not believe and I had thought 90% of that came from the junk I had in back. I have stuff bungee'd to the walls and I figured all the racket had to be coming from junk rattling and banging the walls of the van. A few days ago I cleaned out the entire rear of my van so I could go pick up my new 35" tires. To my surprise I still had all the squeaks and creaks. I kept looking back while driving to see what the hell could possibly making all that noise when there was nothing back there. I figured maybe something had fallen between the sheetmetal reinforcements or something. I dunno, I can't drive and be back there trying to pinpoint the noises too. I accepted it, after all it is a lifted unibody cargo van. I expect it to be noisy.

Well....it doesn't have to be!

After I replaced all four of my black rubber leaf spring bushings (and shackle bushings) with polyurethane....the van is completely silent inside!!!!! Not a peep! It freaked me out! I had no idea all that noise was being transferred into the van from the suspension. I guess those unibody mounts for the springs must have been getting tweaked pretty good. With nice lubricated bushings.... all is silent!

I bought my red poly bushings from Ballistic Fabrication. I used to love that shop and would have recommended them to everyone before they started tacking on a $6.25 "handling fee" to their orders. I understand that fee if you're ordering 100lbs of steel goodies. But I ordered a few pieces of rubber and shipping and handling was over $20. RIPOFF! I can no longer recommend them. But I will post the part number here for reference:



For a van with steel stock or lifted springs, be sure to order the 3" wide bushings. Part Number BUS-650-2 is for the 3" Be sure to order 4 for the springs. I'm not sure if these will work in the stock shackle or Overland shackles..I made my own. I use them in my homemade shackles.

To upgrade you need to remove the old bushings. I did this in a three step process. First I used a two jaw puller from my front end service kit. I put the jaws on the leaf eyelet and pushed out the inner steel sleeve...the one the bolt fits through. Second I used a flathead screwdriver to pry out the rubber bushing. Once those are out of the way you have a steel outer sleeve to contend with. This is the PITA part.

I tried for an hour to cut the sleeve with an air hammer. Forget that. The sleeve is thin and its hard to only cut it and not mess up the spring. I wasted an hour trying. Then I got smart and decided to make some cuts down the sleeve and pry out a section. This is best done with a hacksaw for precision, but can be very carefully done with a sawzall too.

The cuts:



I then jammed a chisel in there and started pounding until that section ripped out:



After a minute with the sledge those sleeves will happily pop right out:





I ordered the cylinder of Prothane Super Grease on ebay. It was like $35. I think they only sell it in this large tube or super tiny packets. The tube seemed like a better deal...the packets seemed to add up quick.

Cylinder seen here all the way on the right side:



I applied some grease to the inner part of the leafs eyelet and the outer part of the bushing. They slid in nice and snug. The bushings have grooves cut in them around where the inner sleeve rests. Those grooves hold grease. Be sure to pack them generously:

(These pix are of my shackles)




Then slide the sleeve through and clean out the excess grease:



Coat the outside of the bushing and the inner sections of the shackles and spring hangers too.

All done:



My van went from sounding like a stagecoach with a busted wheel to a luxury car interior. I'm serious...night and day difference! I'm ecstatic. I'll be doing the same on my other vehicles now too.

Less than $100 spent, maybe five hours labor.....silence is golden. :rockon:
 
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#2 ·
I might have to check into this. I was told the other day that my van dog legs it pretty bad..was asked if I eat up tires and the set I have on now are pretty much ready for replacement and they've been on for less than 20k, so I'd say yes! However, I may just replace the springs as well since I felt the need to put air shocks in the back because the rear swayed quite a bit with a load of people in the van ( 8 adults ). It helped a lot, but I can feel the rear swaying some still when I have it full.
 
#3 ·
Does anyone else sell those bushings? I was getting ready to change my spring bushings with stock Acdelco ones and now that I've seen this I think I better go Poly instead, even though I have new Delcos here!

I'm wondering if someone else makes them so I can get them faster..

Scott
 
#5 ·
I looked around and found some kits from other sellers (for other GM vehicles) but I could not confirm the size of the bushing. Even Ballistics site says the Chevy bushings are 2.5" but that is not correct. Our springs are 2.5" wide but you also need 1/4" shoulder to take up the space between the spring and shackle....or spring and hanger. So indeed 3" wide bushings are needed. If you order from Ballistic don't get the ones for Chevy springs! Get the 3" wide bushings. The other will work but there will be a 1/2" gap between them and that opens up more potential for flexing.

The total length of the bushing should be 3" including the 1/4" shoulders on each end. The bushing diameter should be 1.5" where it fits into the spring eyelet and perhaps 2" for the shoulder (that spec is not as important).

If you can find a Prothane kit or something that has spec's for the sizes you could go by that. I'm certain there must be another seller. Ballistics cost for just the leaf bushings was more than what most full body kits cost. But I pulled the trigger on theirs because I knew the exact dimensions.

I read in some reviews that people recommend the black "graphite impregnated" poly bushings. Maybe they are better. Ballistic doesn't sell those.

I'm sure people will explore and find better, cheaper kits. I just had to post my experience because this cat I could not keep in the bag. If you buy from Ballistic be sure to question them about their bogus handling fees. I told them I thought it was buttrape.

***DON'T FORGET THE GREASE! I USED PROTHANE SUPER GREASE***
 
#7 ·
Unfortunately I replaced my control arm bushings last year with standard MOOG bushings. Had I known better then I would have definItely used poly bushings. Now its too much of a PITA for me to remove the control arms to redo the bushings because of the lift coils. I'll wait a few years before I'll tackle the front. You do need a front end service kit, probably a ball joint press kit, to press out the control arm bushings.

I would ditch the air hammer altogether. Use a saw and make VERY precision slices into the leaf spring bushing sleeves and then just jam a chisel or pound a flathead screwdriver in there to lift and tear out the strip you created with the cuts.

I recommend poly bushings front and rear for ALL vans! I have realllly been enjoying the peace and quiet. Perhaps this weekend I will be doing the poly install for the body bushings as well. So I'll have a review for those soon too!

I also just replaced all of my tie rod boots with energy suspensions poly boots. Not only have they stayed perfectly in place but they also do an excellent job of keeping the grease in the boot where it belongs. I highly recommend those too. I will post a part number for those later today.
 
#9 ·
sfeaver said:
Balistic has a 15% off coupon code right now: extra15 So I'm gonna order those leaf spring bushings. Do they have the ones for the front control arms too? Might as well do it all!

Scott
No, Ballistic just has them for the springs. I think Prothane makes a set for just the control arms. I looked at Prothane for spring bushings but couldn't find a listing for our vans. Though I'm sure they have something that works.
 
#10 ·
UPDATE:

My bushings are still totally awesome, no squeaks at all. The only thing squeaking is my sun visor now. Never even heard it before with all the racket coming from the suspension!

I believe Ballistic is selling Prothane's bushing at markup. Here are the Prothane part numbers for the leaf spring bushings:

Prothane 19-608-BL (for black)
Prothane 19-608 (for red)

Spec's:

Tube length 2.5" (the width of the spring)
Total length 3" (spring width plus 1/4" shoulder for space between leaf and hanger)
Outside diameter: 1.5"
Sleeve length 3"
Sleeve bolt size 9/16"

Cost on amazon.com $22 a set. Be sure to buy TWO sets! One set of four bushings will only do one spring.

I still have not verified the shackle bushing spec's since I'm not using them. If you're feeling brave order ONE more set for the shackles too. Someday I will dig out my stock shackles and measure them....if someone else doesn't beat me to it.

Don't forget:

Prothane 19-1750 Super Grease (packets)

OR

Prothane 19-1751 Super Grease Tube - 14 oz. (way more grease than you will ever need)
 
#11 ·
Now ya post that info! :) I ordered them a week and a half ago, they finally shipped on Friday. Hope to have them by this Friday. There was a discount code on their site, I think I paid about 60 after shipping.

Already got bushings for front control arms. Did you do the fronts too?

Scott
 
#13 ·
Nope! Just did my control arms last year but I wasn't really "in the know" as far as poly went back then. I put in standard rubber Moog bushings. I'm kinda bent now because it's a hell of a lot of work to replace them (HD coils and whatnot).

I'd sure like to have the part numbers for the control arms if you have them handy...

That link didn't work for me.

http://www.amazon.com/dp/B003AVWP0O...TF8&colid=3VJ56HCJZ0KOT&coliid=I2HZ3Q3P1FK7NH

red poly.JPG


OR

http://www.amazon.com/dp/B003AVWP2W...UTF8&colid=3VJ56HCJZ0KOT&coliid=IT1MNRJ81SLQT

black poly.JPG


Copy and paste those...the links might not redirect properly.
 
#18 ·
thegreenmachine said:
Cc, you just bumped my front end budget, now it's gonna cost me 25% more, and shipping to Canada.

Oh well. Lol. Better parts.

Nice info.

Sent from AutoGuide.com App
Ditto!

My rear end sounds like a squeaky mattress full of springs.... Guess when I get some more money after buying my tires and rims I will be buying bushings too
 
#21 ·
97cargocrawler said:
I just ordered a set of the control arm bushings....in case I need to remove my control arms for some other reason, I'll have these ready to go. :dance:
Of course right after I posted that I noticed my control arms were broken. I have been running the Prothane control arm bushings top and bottom now for about two weeks. My arms are highly modified and they're keeping a 35" tire from wobbling....so far I'd say the poly bushings are doing a pretty damn good job. I can't really comment on the difference between the poly and Moog that I had on there previously since everything feels different with the new unbroken arms and larger tires.
 
#26 ·
That shoulder rests on the outer edge of the hole on spring pack so it can only go in so far, and rests against the shackle on the other side so that bushing isn't moving anywhere. You could an appropriately sized washer in there to fill in the gap if it really bothers you. But f those bushings were one piece, it would be impossible to install.
 
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