noise from new subframe connectors?
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I just put on some subframe connectors, umi weld in boxed sfc's.
http://www.umiperformance.com/2000.aspx
my car is an 02 formula, with 30k miles, and is stock other than the sfc's
I had a local shop weld them in per recomendation from a few people on FAST. The second I drive it out of the shop I hit a bump, and it makes this big knock noise. I call the shop, they say its normal and its just the trailing arm (LCa) bolts breaking in (the sfc's came with new bolts). he said it would be done with after a few good bumps. It has stopped mostly, but if I hit an especially large bump or just hit one wrong it will still do it. On the drivers side, it sounds like its coming from the rear, and its a loud knock. On the passenger side, even more rarely it is a clunk noise, also from the back.
I have checked and there is nothing it should be hitting. It has 1-4 inches clearance from the floor board in most places. It is close to the driver side rocker panels, that skinny rail on the bottom of them, but I dont think that could cause this. I looked at the shocks, springs, exhaust, lca's, panhard bar, and everything is fine to the best of my knowledge.
I put it up on a stand under the differential and tested how tight the bolts were. my torque wrench was too big, so I just used a small socket wrench. I could not tighten them at all, but if I didn't have a wrench on the nut the whole thing would spin easily.
Does anyone know what could be going on or what I could do to check/ fix this?
http://www.umiperformance.com/2000.aspx
my car is an 02 formula, with 30k miles, and is stock other than the sfc's
I had a local shop weld them in per recomendation from a few people on FAST. The second I drive it out of the shop I hit a bump, and it makes this big knock noise. I call the shop, they say its normal and its just the trailing arm (LCa) bolts breaking in (the sfc's came with new bolts). he said it would be done with after a few good bumps. It has stopped mostly, but if I hit an especially large bump or just hit one wrong it will still do it. On the drivers side, it sounds like its coming from the rear, and its a loud knock. On the passenger side, even more rarely it is a clunk noise, also from the back.
I have checked and there is nothing it should be hitting. It has 1-4 inches clearance from the floor board in most places. It is close to the driver side rocker panels, that skinny rail on the bottom of them, but I dont think that could cause this. I looked at the shocks, springs, exhaust, lca's, panhard bar, and everything is fine to the best of my knowledge.
I put it up on a stand under the differential and tested how tight the bolts were. my torque wrench was too big, so I just used a small socket wrench. I could not tighten them at all, but if I didn't have a wrench on the nut the whole thing would spin easily.
Does anyone know what could be going on or what I could do to check/ fix this?
Last edited by fadetoblack6902; 07-02-2005 at 01:23 AM.
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Ok I had the same problem with my BMR weld-ins. I drove off after the install and heard a clunck/rattle, kinda like my door was open and rattling (sound). So I immediately took the car back to the shop and we discovered there was some play in the sfc to lca connection (the bolt wasn't tight enough). The bolt need to be torqued down some more, which in turn smashed or closed the gap that was there. After that fix everything was fine, no more problems.
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I want to get SFC's for my Camaro, but I wanted to get the bolt on version. Would a problem like this show up more with a bolt on SFC since there are more bolts involved?
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Originally Posted by JJ2002
I want to get SFC's for my Camaro, but I wanted to get the bolt on version. Would a problem like this show up more with a bolt on SFC since there are more bolts involved?
I would assume so. The bolts can come loose. Just get welds dude.
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I want the bolt on because I don't want to lose the resale value of the car by having a permanent mod. And the DD SFC's take a lot of room so if I decide to get smaller sfc's for more room I can easily remove them. I agree weld in is the best way to install...but for me bolt on is what I need.
So what was causing the noise, was it a loose bolt or a weak weld?
So what was causing the noise, was it a loose bolt or a weak weld?
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Originally Posted by JJ2002
I want the bolt on because I don't want to lose the resale value of the car by having a permanent mod. And the DD SFC's take a lot of room so if I decide to get smaller sfc's for more room I can easily remove them. I agree weld in is the best way to install...but for me bolt on is what I need.
So what was causing the noise, was it a loose bolt or a weak weld?
So what was causing the noise, was it a loose bolt or a weak weld?
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Originally Posted by joblo1978
Why mod a car you don't intend to keep then? If I found a used F-Bod with SFC's, that would just make me more inclined to buy it. Trust me, you won't lose any money on resale by adding SFC's. Hell, most wouldn't even realize they weren't stock. They help hold the car and preserve it. Ask some about what not having SFC's can do to out cheaply made F-Bodies. A test drive by a salesman on an F-Body with SFC's would say, "Hmm, drives good, nice and solid."
The thing is, some people get rattles and others haven't had a problem with the bolt ons. What's everyones experience?