*Thump* during excessive braking, after many new parts installed.

Hola! So me and a friend swapped a front traction bar in, whith new front trans mount, along with new rotors and pads into my DA last night. All feels great except for when I brake hard. If I slam on the brakes going roughly 20mph I get a massive thump in the front, just one time, and I can’t pinpoint the location. I’m going to jack it up later to examine and hope something is loose, any ideas while I’m under there?

Did you make sure you torqued all the brake bolts down to spec? Could be a loose caliper slamming against your rotor cause it’s not tight enough?
Jack your car up, take off your wheel and spin the rotor then have your friend step on the brake and see if the thump is from there. If not, check the torque specs for the traction bar.

My cousin had the same thumping noise after a traction bar install and it turned out to be some loose bolts. Good luck.

definitely check to make sure that traction bar is tight. also check that the radius rod ends(sphericals) are as striat as posible between the 2 tabs on the bar and where it mounts to the LCA.

Yeah, this is most commonly an issue w/ the traction bar not being tight enough on the chassis. It’s happened to almost everyone I’ve talked to. Seems you gotta tighten 'em, drive it, and re-tighten. But of course it could be something else, like calipers as hybrid90 stated.

Glynn, how happy were you with your FR bar in regard to the sphericals being straight like you mentioned? I’m quite unhappy with the overall design of my FR. My forks hit the radius rod mount on the control arm and the radius rods are not as straight as they should be where they mount - looks purely like the angles in their jig need to be changed. If I wasn’t so lazy and I had more of a workshop to use I’d ditch it in favor of a modded stock crossmember in a heartbeat.

Thanks for the responses guys. But i guess im not quite sure what you mean by making them as straight as possible between the 2 tads on the bar and the LCA mounts?

This bar was previous on a DA so i did nothing to adjust it to fit mine. It seemed to fit fine in mine so i didnt adjust it. The Rods do not move back and forth at all, and they are only able to turn side to side due to the bearings (one side turns a little bit easier than the other but still no big deal i wouldnt think)

I have no idea what could be the issue here. Last night i jacked it up and re-tightened every bolt again to be safe. The main traction bar bolts went a little tighter but nothin that i thought would cause any problems prior.

Ive also notice a creaking noise when i come to a stop now… Im at a loss! When we swapped the front brakes and rotors we did have to compress the caliper because the pads on the car were super low and the new pads were… well new. When we compressed them, fluid overflowed out of the master cylinder and onto the floor since we were forcing fluid back out by compressing. I wonder if that caused any damage to the master cylinder or something?

spilling brake fluid wouldnt cause anything like the problem your having, I do hope you cleaned it up really good thought as it is horrible for your paint!

I hadnt notice that the tab are not parallel to the radius arms but even if I had, im sure I wouldnt have given it a 2nd thought. I figured the helm joints would be able to compensate for that difference in that angle. To my knowledge I dont have that problem with my shock forks either. however. I am getting and have been dealing with for quite some time, the sound as described in this very thread. I swear its my traction bar thats loose. ive even gone to the extent of replacing all 6 tow hook bolts with brand new oem bolts and replacing the 2 main bolts with ones that are stronget grade 10(fully hardened) over the ones full race provides(grade 8, outside hardened). Im starting to think that maybe its my radius arm twisting and making contact with the 2 tabs on the bar or the bracket at the LCA. I need to figgure this out soon as my open track day at high plains is coming up fast! and well it is extremely anodizing when I just want to take the car out for a drive. I can totally understand why you would want to just run a modded stock crossmember, this is getting to a point where im ready to consider the same…

it sounds like its the heim joints, especially if the bar was used. try lubing them.