Prothane Coil Bumps
#31
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Year: 2000
Model: Cherokee
Engine: 4.0
Here's what I'm working with now:
I had a poly bump bolted to that metal piece, hitting the old plates like you pictured. But upon redoing the whole rearend I decided to try progressive. So I bought the prothane rears, and the DBO plates, and will most likely cut off that box that's on the frame rail and just use 1/4" flat stock welded there as a strike plate.
I had a poly bump bolted to that metal piece, hitting the old plates like you pictured. But upon redoing the whole rearend I decided to try progressive. So I bought the prothane rears, and the DBO plates, and will most likely cut off that box that's on the frame rail and just use 1/4" flat stock welded there as a strike plate.
#32
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Year: 1999
Model: Cherokee
Engine: 4.0L I6
Has anyone tried putting these between the spring and axle while still using the factory plate on top. If needed you could also have a shop mill it to be used as an angled shim.
#33
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Year: 1991
Model: Cherokee
Engine: 4.0 HO 153k
Front 10.5" Prothanes mounted free in coils. I welded a larger washer to base of stock bump tower.
Daystar upper bump stops. 2.5" trailer hitch tube welded to axle tube with 1/4" plate welded on top (level with spring plate). RE front coil bump stop added for adjustment.
Daystar upper bump stops. 2.5" trailer hitch tube welded to axle tube with 1/4" plate welded on top (level with spring plate). RE front coil bump stop added for adjustment.
#34
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Year: 2000
Model: Cherokee
Engine: 4.0
Wanted to update with what I ended up doing for now.
Got the Dirtbound u-bolt bump plates in the mail, and mounted them up, with the 4.5" Prothane progressive bump. I am concerned about what Steve said and will most likely have some 1/4 flat stock welded to the bottom frame to spread the force of the bump contact. And if I ever change my setup I can drill and tap that flat stock for a different bump.
I'm also worried about the u-bolt plate itself. I had DPG plates for the 8.25 on a previous build and they had a gusset on them, but I forget the plate thickness. DO you think I should be worried about these plates bending from force?
As you can see I had a lot of bump to make up for, I could have had something welded to the tube, but just decided to try the cheaper route since the welding would have cost me more than the plates.
Got the Dirtbound u-bolt bump plates in the mail, and mounted them up, with the 4.5" Prothane progressive bump. I am concerned about what Steve said and will most likely have some 1/4 flat stock welded to the bottom frame to spread the force of the bump contact. And if I ever change my setup I can drill and tap that flat stock for a different bump.
I'm also worried about the u-bolt plate itself. I had DPG plates for the 8.25 on a previous build and they had a gusset on them, but I forget the plate thickness. DO you think I should be worried about these plates bending from force?
As you can see I had a lot of bump to make up for, I could have had something welded to the tube, but just decided to try the cheaper route since the welding would have cost me more than the plates.
#35
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Year: 1998
Model: Cherokee
Engine: 4.0 HO I6
That's my concern with the extended ubolt plates. Yes it's 3/8" thick, but it's still basically being use as the fulcrum to force the axle to articulate, which has to be a lot of force. I'm concerned it will bend the plate (I feel like I've seen someone post about a setup like this bending). I'm still looking at options for how to set up the rear of mine. You could always just take a piece of 1/4" plate as a kicker down to the axle tube - that should give it enough support to not bend.
#36
Beach Bum
The guys that race their XJs support the cantilevered plate with a 'stiff leg', 2" or 3" diameter pipe run vertically between axle tube and plate. This not only prevents the plate from possibly bending, also eliminates the strain on u-bolts when plate is impacted.
With that said, If that plate is bending than an unprotected unibody rail will likely have worse damage.
With that said, If that plate is bending than an unprotected unibody rail will likely have worse damage.
#37
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Year: 2000
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The guys that race their XJs support the cantilevered plate with a 'stiff leg', 2" or 3" diameter pipe run vertically between axle tube and plate. This not only prevents the plate from possibly bending, also eliminates the strain on u-bolts when plate is impacted. With that said, If that plate is bending than an unprotected unibody rail will likely have worse damage.
#38
Beach Bum
Sounds good. Can mark bump with chalk to see where it contacts, if it contacts at all, and how much it spreads out.
I suggest securing that brake line. Hard line, union, and soft line (since soft line does not move).
I suggest securing that brake line. Hard line, union, and soft line (since soft line does not move).
#39
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Year: 2000
Model: Cherokee
Engine: 4.0
Yeah I need to have the little brackets tacked to the axle tube still, I need a few things tacked as well so I'm going to get them all done at once. I took it on some whoops an hour or so ago. They did good, no bottoming of shocks going 20-25 mph, no other noises that would indicate contact anywhere. I like that chalk idea, I'll have to do it when the snow is gone so I can actually see the contact marks.
#40
Beach Bum
Bottom Out
So, I bottomed out hard at 30 mph. Cap was pushed up into coil and wedged there. Strange thing is, when i got back home cap was back in proper position, seated in prothane.
#41
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Year: 2000
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So, I bottomed out hard at 30 mph. Cap was pushed up into coil and wedged there. Strange thing is, when i got back home cap was back in proper position, seated in prothane.
Bottom Out - YouTube
Bottom Out - YouTube
This thing wasn't built for jumping, it's loaded down with all kinds of armor and other stuff. But the fact it took that jump like a champ and was so smooth on landing, tells me I built it well, and the bumps wokred haha. Now for a trussed 30.
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