Split : RPM/Mike Lee/SyTy Perf

jjorgensen52

NHSTE - I'm the only one!
Just got a picture from my Dad, he drove my Ty yesterday from NH to Cape Cod and somewhere along the way near Boston this happened:

brokenaarm.jpg


3 year old RPM arms with about 3500 miles on them. It's not broken off, to the arms credit it made the remaining ~90 miles of the trip like this, but still sucks.

Just for reference, not flaming RPM or Mike (will be calling him tomorrow when the shop opens) in any way, just ticked that my truck is broken AGAIN. Not 300 miles after I blew apart my lifters and had to rebuild the engine. :rant:
 

mattw

Active member
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

Wow, thats kinda scary.. Makes me think that sticking with the ugly stock lower arms probably isn't such a bad idea..
 

bezerk

New member
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

i feel safe with the budget coilover now.
 

43t_ftw

Member
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

i feel safe with the budget coilover now.

haha ya.. makes me feel better about my decision to be a cheap ass and keep the stock a arms :rotf:

shitty luck tho man, hopefully rpm will do something to help you out..
 

JSM

Active member
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

Ok, I am responding purely from an engineering standpoint and to ease the minds of anybody running JSM arms.

There is a major difference in the design/construction of the 2.

RPM felt it was important to duplicate the stock GM ball joint angle, in doing so the flange had to be different. This involved putting a bend in it, and shortening the tubes. You can see that on his webpage.

LINK


On my design I changed the balljoint angle for several reasons. 1 it made the design easier, it allowed me to make the tubes longer and support the balljoint better.

LINK TO JSM ARM DESIGN


So those with JSM arms will not have this issue. I have a truck in my driveway with my arms on it and the owner is guessing it the arms have around 100k miles on them.

JSM customers continue to sleep just fine.
 

BigBadSmoosh

Picking fights on I-65 since 2013
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

obviously a design failure.. going to be an expensive replacement for the manufacturer. either that or he just should not sell them to anyone in the northeast.

usually stuff like this is cause for a recall of all of the parts designed this way.

OUCH.

glad you made it home safe, and hopefully there isn't any further damage to the truck.
 

Jimmy

Banned
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

Ok, I am responding purely from an engineering standpoint and to ease the minds of anybody running JSM arms.

There is a major difference in the design/construction of the 2.

RPM felt it was important to duplicate the stock GM ball joint angle, in doing so the flange had to be different. This involved putting a bend in it, and shortening the tubes. You can see that on his webpage.

LINK


On my design I changed the balljoint angle for several reasons. 1 it made the design easier, it allowed me to make the tubes longer and support the balljoint better.

LINK TO JSM ARM DESIGN


So those with JSM arms will not have this issue. I have a truck in my driveway with my arms on it and the owner is guessing it the arms have around 100k miles on them.

JSM customers continue to sleep just fine.

Are you saying that RPM ripped off your design,then modified it to fail?


WOW. :roll:
 

MRKING

New Parts for Old Trucks
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

I love jeff like everyone else ( maybe more than you know, hehe ) , but why were the js arms even mentioned in this thread ? maybe some thread cleanup is in order .
 

MikeRenz

not stock
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

I love jeff like everyone else ( maybe more than you know, hehe ) , but why were the js arms even mentioned in this thread ? maybe some thread cleanup is in order .

so that those using his a-arms can rest assured that the manufacturer of their product are standing behind their design
 

MRKING

New Parts for Old Trucks
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

so that those using his a-arms can rest assured that the manufacturer of their product are standing behind their design

well i didnt pay for em so hopefully they were worth that much .:lol: but the reason i aquired them is not really helpful to mike case really. a local kept blowing out drivers axles (at least 3or4) and traded me his front kit for my modified stock setup . he thought the arms were bad and was tired of dealing with it .
 

JSM

Active member
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

I love jeff like everyone else ( maybe more than you know, hehe ) , but why were the js arms even mentioned in this thread ? .

I love you also in a Normal way though.

Reason I posted is because some where asking me about my a arms, and I was worried, etc.
Tryed to explain the differences as best and neutral as I could.
 

gkrcr882

SyTyless......for now!
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

I love you also in a Normal way though.

Reason I posted is because some where asking me about my a arms, and I was worried, etc.
Tryed to explain the differences as best and neutral as I could.


That's the vibe I was getting, that not all aftermarket control arms are created equal, and therefore may not experience the same problems. I'm sure RPM will figure something out- heck, they might even like to see the arm to improve on the design for in the future. Part of the R&D of a product is failure analysis :tup:
 

jjorgensen52

NHSTE - I'm the only one!
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

shit , i started the stock arm swap revolution and just recently did the rpm arms to save the extra weight . i hope it was a wise choice . people have been running them for years so far , so im not really worried .

This just jumped out at me, I don't know if it makes a difference but these arms are one of the very first (there were 10 sets made, I believe, in the first run) from RPM. It appears they have since reinforced the lower arms, but I can't say for sure.
 

skipztt

boost
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

IMO those a-arms are junk. they look cheap.
 

blk00z28

Forced to by choice
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

So in other words if your set were in the first batch of arts made, they could have been considered in the prototype stage still? Then the second design, or the current ones are the corrected version based off the testing of your set(s).

I'm not hating on anyone. And do not accuse me of that. This is my opinion in which I am trying to see both sides and not lean on any which person. I've only seen one aftermarket a-arm set on a truck in person, and I think they were the very first set made by Jeff(I could be wrong). They looked nice, and that I know of are still in good condition on a running truck. But you've got to really ask this. How many kits of these have been sold, and are actually in use? Now, what's the failure %? AND, what is a acceptable failure % on parts like this? The only way to figure that out would be to take every person who has bought them(and actually uses them..) and take their arms and find out if they are still "correct." Because what if this turns out to be the one and only case? Or if others who have made arms have one person have some type of failure with their arms and everyone slits his throat too.

Because of the worry of a future like this on aftermarket a-arms is why I've stuck with the stock setup. But like I said above, even from the factory they factor in a % for failure. Granted, that % would be smaller due to the number of units sold/made. But not everything is perfect. And because there are not a lot of these sold by any of the arm makers on here, the % is going to be a lot higher just based on no real long term testing. Remember the auto makers have million dollar machines that simulate road conditions for long term testing, and then build the final. We have to rely on ourself in this group to test things like this.

I'm pretty sure over the years people have had problems with a stock arm bending at some point somewhere. Either it be in a normal S truck or one of ours. So to just jump right off saying its a bad product is a little harsh without further details, and at least a response from the person who made them. (and to say they haven't replied is wrong, its a weekend when this was posted.. Not a lot happens on here on weekends..)
 

jjorgensen52

NHSTE - I'm the only one!
Re: Can't catch a break - broke an a-arm

Re: Can't catch a break - broke an a-arm

JJ any update?

Yes. Spoke to a tech at RPM this afternoon and have consequently emailed back and forth with Mike.

These arms were in the first run (as I stated), and Mike told me that since then, as I suspected, the design was changed to include a reinforcing gusset on the ball joint plate to prevent this issue from occuring.

Once I am able to remove the arms, RPM is going to repair/update or replace the arms to the new design with the gusset (for whatever it costs me to ship the arms back to them).

On the whole, I'm still ticked my truck is broken but I'm happy with the way this is being handled and I'm confident that the updated arm design will eliminate this problem.
 
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