Snapped Rear Shock Mount

[MattandOrange]

Just got my CJ7 lifted 2.5. The rear passenger side's u-bolt plate completely snapped at the shock mount. They were factory and couldn't take the compression of a new shock.

Q1) So while I wait for new u-bolt plates to arrive, can I still drive it or should I wait?

Q2) If I can drive it, is there a distance that I should stay within?

Q3) Are the factory replacements sufficient for occasional driving and mild wheeling or should I get a stronger aftermarket set of plates.

Thanks!

 

[gert]

Just got my CJ-7 lifted 2.5. The rear passenger side's u-bolt plate completely snapped at the shock mount. They were factory and couldn't take the compression of a new shock.

Q1) So while I wait for new u-bolt plates to arrive, can I still drive it or should I wait?

Q2) If I can drive it, is there a distance that I should stay within?

Q3) Are the factory replacements sufficient for occasional driving and mild wheeling or should I get a stronger aftermarket set of plates.

Thanks!

Q1-2 just be careful as the rear will now bounce better

Q3 the stock will do fine for mild wheeling

I do not know what you know so my question to you is did the mount fail from the wrong length shock? when you lift jeep you need to check your shock travel versuses max spring up/down flex to make sure your shock dosent become your axle stop and possibly rip off another hanger

 

[MattandOrange]

Q1-2 just be careful as the rear will now bounce better

Q3 the stock will do fine for mild wheeling

I do not know what you know so my question to you is did the mount fail from the wrong length shock? when you lift jeep you need to check your shock travel versuses max spring up/down flex to make sure your shock dosent become your axle stop and possibly rip off another hanger

I got the 2.5 Rancho kit with the corresponding RS5000s. I checked the part numbers a few times over to make sure the application was correct. I think the ubolt plates were just really worn out.

 

[gert]

very cool then you will be fine after a new plate

 

[PaRenegade]

Shocks are more for bounce / cushioning so you should be fine for driving on the pavement but stay off the bumpy roads or trails till you fix it. But for a shock to bottom out hard enough to tear off a welded stud from the ubolt plate, I would almost bet money the shocks are too long or more likely your bump stops are missing. That shock HAD to fully compress in order to put any more downward stress than normal. Even a stiff shock has some give, unless it has no more room to give.
Theres nothing to "wear out" on a spring plate. A weld had to break or the shaft had to shear. And that takes some force to do.

 

[Old Dog]

just a guick ? were you wheeling it when it broke. As others have said, sometimes the shockes that come with kits are to long. I know the ones that came with my 4" kit were.

 

[MattandOrange]

@Pa & Old Dog

Interesting. I actually called Rancho to make sure I had the right part numbers. Of course, I'm only comparing the numbers on the box. I didn't see part numbers on the actual shock. I don't exactly know when it broke. I noticed it when I walked up to the Jeep the morning after I lifted it. Wasn't wheeling at all, but I cruised on the freeway for 75 miles or so.

The way it broke almost looks like it tore off. I'll take a picture tonight. It's kind of gnarly.

 

[IOPort51]

Did you put longer bump stops on it?? Even with the new shocks you do not have any more travel, just more length. I would bet lunch that you bottomed out the shock. You will have about an inch of upward travel before it bottoms out the shock and right now your bump stops are about 3 inches away from the axle.

Don't let this bother you too much as the downward travel is what you are really interested in. The upward travel needs to be Limited to keep the tire out of the sheet metal.

 

[thiswontbetooexpensive]

If it helps any, both stock plates on the rear of my CJ were broken in the past and re welded at some point. This was before the PO took ownership some 20yrs ago. They were still holding up, but new ones were pretty cheap as far as what they accomplish for you...I have two new ones in a box for reassembly.


This won't be too expensive Dear! That's what I keep saying. Over and over again.

 

[thiswontbetooexpensive]

Plate, Rear Spring To Axle, Driver's Side 5363439

Right Shock Spring Plate 5363440

These seem to what you might need, there are different part numbers for right and left. I would also look into what has been mentioned about the bump stops and shock measurements.

 

[BusaDave9]

If you drive your jeep at all make sure you remove BOTH rear shocks. Having only one on an axle is much more unstable than having both missing.

I would almost bet money the shocks are too long

As others have said, sometimes the shockes that come with kits are to long. I know the ones that came with my 4" kit were.

@Pa & Old Dog

Interesting. I actually called Rancho to make sure I had the right part numbers.

as IO and others have said your shocks are too long. If you followed the manufacturer recommendations you will probably bottom out your shocks and till never come close to topping out the shocks. I never go by manufacturer recommendation. They will give you the wrong shocks every time. I measure my extended and compressed lengths myself and then buy shocks that match MY measurements.
I too have destroyed rear shock (spring) mounts and front shocks when using what the manufacturer recommended.
I drove my CJ into a ditch to compress opposite tires to come up with compressed and extended lengths.

You can extend your bump stops but I prefer maximum travel. All that takes is making your own measurements.


EDIT: here is Rancho's specs for shock extended and compressed lengths:http://www.gorancho.com/assets/catalog/Specifications.pdf

 

[MattandOrange]

Did you put longer bump stops on it?? Even with the new shocks you do not have any more travel, just more length. I would bet lunch that you bottomed out the shock. You will have about an inch of upward travel before it bottoms out the shock and right now your bump stops are about 3 inches away from the axle.

Don't let this bother you too much as the downward travel is what you are really interested in. The upward travel needs to be limited to keep the tire out of the sheet metal.

I didn't put longer bump stops, but I will when I get the new spring plates in. Bump stops are also called axle snubbers right?

 

[PaRenegade]

Yes. A pack (Prothane) of 4 is like $16 at 4WDInc.

 

[MattandOrange]

Here are the photos. I think maybe the u-bolt plate tore on shock extension because the ripped plate's edge moves upwards and not downwards. Also the ripped shock mount had rotated clockwise away from the rest of the plate.

What do you guys think?
Are YJ rear spring plates the same as CJ7 rear spring plates?

 

[Torxhead]

Yikes, I would not even start that thing up. The u-bolt in the first pic is ready to let loose. There are aftermarket skid plate /u-bolt pad/shock mounts that are a lot more heavy duty you might want to check in those:cj u-bolt skid plates - Bing Images