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Leaf Spring mounting plate and Bump Stop

Black1990jeep

NAXJA Forum User
Location
california
For my lifted XJ I am putting on rear rebuilt springs. I see there are combination leaf spring mount plates and bump stops made by two vendors...

https://dirtboundoffroad.com/products/rear-u-bolt-spring-plate-and-bump-stop-mount-jeep-cherokee-xj

and

https://dpgoffroad.com/product/dpg-adjustable-bump-stop-plates-xj/


dpg and uses a flat 3/8 inch plate. it has a gusset to stiffen the over hanging bump stop portion of the plate, but no bent edges to stiffen the spring plate section

Dirt bound also uses a 3/8 plate but has reinforced bent edges for added stiffness of the spring plate, but no gusset for the bump stop portion of the plate

So neither has both features, one stiffens the the spring plate area, the other better supports the bump stop area.

How do these compare?

Are there other vendors than these two that make a combination spring mount and bump stop?
 
I've had the Currie ones, and bent them. The whole top plate bent, deformed around top of the leaf spring. Both of them. A little thicker material and they would survived. It's a shame because the design is pretty cool.
I currently have the Dirtbound ones and so far so good, but haven't thrashed them too hard yet.
 
Seems like a resourceful person could use the Dirtbound plates and fab some gusseting similar to the Currie design to minimize bending.

Or it you have an longer anti-wrap spring perches like I run, you could extend a vertical gusset plate from the bottom of the spring plate to spring perch and bolt through the inside face of the spring perch, which would prevent the bump area of the spring plate from bending and also better distribute the shock load from the bump stop.

000_0369.jpg
 
ok, I now see the Currie built spring plate/bump stop. It appears from photos it is made of 1/4 inch plate, is that correct? I am concerned with Ronbos comment on how these bent.

so maybe 3/8 inch plate should be a minimum thickness, with bent edges?

Now I am thinking maybe it is not such a good idea to make the bump stop part of the spring plate. If you bump with enough force, things may give, U bolts stressed as the bump stop load is offset so much, that plate will want to twist.

Maybe it is better to place the bump stop on the axle tube, rather than the spring plate?

Comments on this?
 
I’m running some leaf plates that I bought years ago from someone on NAXJA. I don’t recall who made it. I like that the extension that contacts the bump stop is raised above the height of the leafs. It’s held up remarkably well, probably because I don’t do any high-impact go-fast driving. Here’s a picture:

304e2ea1471a2b73dc9c16546e753ae1.jpg
 
ok, I now see the Currie built spring plate/bump stop. It appears from photos it is made of 1/4 inch plate, is that correct? I am concerned with Ronbos comment on how these bent.

so maybe 3/8 inch plate should be a minimum thickness, with bent edges?

Now I am thinking maybe it is not such a good idea to make the bump stop part of the spring plate. If you bump with enough force, things may give, U bolts stressed as the bump stop load is offset so much, that plate will want to twist.

Maybe it is better to place the bump stop on the axle tube, rather than the spring plate?

Comments on this?

I have the Dirtbound plates. I have not bent them.

I have thought about adding support between them and the axle tube however. From a manufacturing perspective that could be a bit of a pain because of variations in the thickness of leaf spring packs. Might be feasible with something threaded for adjustability. For a fabricator it is just a matter of welding something in that spans the gap between the plate and the tube.

What has held me back is the fact that to do it right I will be replacing the U-bolts. Since I don't have any other reason to take off the U-bolts I haven't made a priority of the task. It is just one of those things that sits on the back burner, waiting for a chance to be part of the scope creep of another project.
 
I’m running some leaf plates that I bought years ago from someone on NAXJA. I don’t recall who made it. I like that the extension that contacts the bump stop is raised above the height of the leafs. It’s held up remarkably well, probably because I don’t do any high-impact go-fast driving. Here’s a picture:

304e2ea1471a2b73dc9c16546e753ae1.jpg

Looks like a strong and effective solution.
 
I use the dirtbound units with a solid bump stop on the frame. I spend a lot of time bouncing off those stops as for some reason my jeep destroys any leaf packs i put in there. Havent bent them yet.
 
OCD much ? I have stock leaf spring plates on my 5.5" lift.

Buy the Dirtbound and add a gusset, or make your own out of 1/2 inch plate if you think that is necessary.
 
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The elastomer inserts look like the ones used in inexpensive mountain bike front shocks.
It might be a better choice than solid rubber bump stops in that it is adjustable, using inserts of differing stiffness. Interesting way to get some of the benefits of a hydraulic bump stop without the huge expense.
https://www.summitracing.com/parts/...MI49vTmeTH6AIVA9lkCh0t7QulEAQYAiABEgJuD_D_BwE
 
Installed the 5/8 dia. U Bolts, torqued to 170 ft lbs, and found my 1/4 inch spring plate folded like paper!

So I bought some 3/4 inch plate to make my spring plate out of. I dont think it will bend, I will let you know if it does.
 
Installed the 5/8 dia. U Bolts, torqued to 170 ft lbs, and found my 1/4 inch spring plate folded like paper!

So I bought some 3/4 inch plate to make my spring plate out of. I dont think it will bend, I will let you know if it does.

According to the workshop manual, those (OEM) U bolts should be 52 ft. lbs. On my XJ I have 1/2 inch bolts with fine thread and tighten them to 70 ft. lbs. At 170 you could be asking for trouble.
 
I never liked the u-bolt spring plate as the bump stop mount.

I added 1/4" 2x2" steel tube to the axle housing with a 1/4" top plate with threaded nut to add pucks as needed to adjust spacing.

Bumpstop%20tower_zpsz6kxmgsi.jpg

Tower%20on%20axle_zpscj2ab8cc.jpg

Tower%20flush%20to%20spring%20plate_zpsgyxksu3x.jpg

Tower%20with%20puck%20and%20upper%20bumpstop_zps51libxkz.jpg
 
5/8 inch grade 8 U bolts get 170 ft pounds, but evidently you need a stronger plate for that. The axle and springs can handle it.

I am not question the ability of the bolts to take 170 ft. lbs. I question the ability of the axle tube to withstand that amount of pressure.

Then again, I do not know much about axle tubes. I do know that that puny XJ D44 axle tubes in the back of my XJ probably would not be able to withstand that much without crushing at the U bolts.
 
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