so I installed my lowering springs on my 2011 gt and now everytime I hit a serious bump or go over a speed bump without coming to a dead halt, the rear end sounds like its bottoming out or smacking something. has anyone had this problem? is it ppossibly the stock shocks being too soft? or not having enough travel and now it's bottoming the shocks out? i called American muscle and they said i shouldn't need anything at all. the **** is going on lol.
S&r springs, causing rear-end noise
- Thread starter poisonova
- Start date
Did u change out the bump stops
I have these springs on my 2013. I had to chop the stock bump stops in half. Not sure exactly what you were told but you WILL HAVE TO either cut the stock ones in half or buy aftermarket jounce stops that are shorter. I used a hack saw to cut mine in half. Only issues I had was the stock front strut mounts are junk one time use only. Had to tear everything back down and install koni's with gt500 mounts
I wondered about that. I bought a set of FRPP stops but didn't install them because I saw they were the same height as the stock ones, plus you need some sort of funky tool which I don't have to remove them. I figured maybe they were the same because mine is a Boss, but you're saying they have a different compression rate? I think they are a different color.
yes the frpp are softer but not by much. the tool can be bought at the auto store for cheap, you just need the socket end and connect it to a ratchet.
yes the bump stops. from the bottom up, i cut mine at the first lip.
the fronts are different that's why. The fronts are on the strut itself and are smaller already. because the rears sit so high, thats why the bump stops are high as well.
How do these springs ride. ....are they bouncy
i just cut both lips off completely. mine is just the bottom flat portion.
The FRPP as far as I can tell, are the same as the stock ones. They feel the same, after having been on the car for 6 months they look the same as the stock ones, having turned a dark dirty brownish/yellowish color.
Also the tool needed is a T45 tipped socket. I picked one up today because I am going to reshape my bump stops with a file to be rounded again and lost my old one.
Was $2 at Home Depot.
Also, I forget what the SR springs drop the front, but if it is 1.5" or so, you need to cut the front bump stops too. I am dropped 1.7" in the front and my front ones were crushed at the stock height. THey are now maybe a 1/4" tall and the front doesn't bottom out anymore.
When they were the full size, the car literally sat on the bumpstops at ride height.
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the website says it's a 1.5 maybe a tad less in the front. but I haven't had a single issue up front with anything. you don't need the tool to pull the stops off do you? maybe I'll just cut them off while it's still on lol
Yeah, you should still check them, your front end probably doesn't have much travel. If you suspend the front end so the suspension isn't loaded, lift up the dust cover and look at the bump stops, they will probably look imprinted and bent up from the car literally sitting on them.
Mine did anyway.
You don't need to remove them to cut them(rear that is, front are near impossible to cut without risking cutting the struts which can damage them), just know they are a PITA to cut is all. I found it easier to remove them and take a dremel tool to them. You could cut the rear ones with them on the car though with a razor blade, just be patient so you don't rip yourself open haha.
Just cut the stockers in half. No need to remove them. Just pull the wheels and start cutting. I did this with jack stands under the rear axle with the suspension loaded so I could have a good idea of how much to cut. I could clearly see with the wheels off I had almost no upward travel in suspension before the stops hit the c-notch. I simply just cut them in half. No worries and no $$ out of pocket. 10k+ miles and no issues. I run 255/35/20 tires on all 4's and don't rub anywhere and there is still enough meat on the stops to still be effective
Also no modifications are need to the front stops with these springs. They are 1.5in drop on all 4 corners. I later installed the koni's which dropped another half inch or so in the front due to a shorter distance between the spring perch and knuckle bolt holes on the 05-10 spec koni's. I simply swapped the boot and stops over to the koni's. nothing bottoms out or makes noise. The handling and ride is night and day with these springs/stock/shocks/struts vs these springs/koni's. in a good way lol
I checked again and it just requires a T40 (not 45) Torx tip socket so I borrowed one from a friend and swapped them. The FRPP part# is totally different than the stock bumpstop's. H&R has an interesting explanation of the function of what they call "micro cellular jounce bumpers".
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