MYCoupe

Not sure what your issue is, but I have been reading this entire thread from the beginning. I was merely pointing out to the OP that I went from his previous setup to his current one without any issues when it comes to tire diameters. Not sure what is so hard to follow about that for you...

weathermaker

Would it be foolish to swap out 1 at a time and drive it around the block and see if 1 of the tires are the culprit?

cgladish

if you haven't already, why not take them to a tire shop and have the balancing checked? if they check out, then the issues becomes something on the car. at least then you know what problem to chase.



go get 'em tiger!

Jclgodale3

these are freshly mounted and road force balanced. 2 drives in the subdivision at maybe 1 mile and not over 30mph

jkirk1

Complete guess here, but is there any chance the wheels are not pulling down all the way on the hub? Are the lug nuts closed end and bottoming out before pulling the wheel up tight? Maybe the newer style wheels allow the studs to stick out further from the wheel.


Sorry, just trying to think of anything that may help.

Jclgodale3

thank, ill take any possible solutions at this point. I️ am, however, confident the lugs are pulling the wheels tight to the hubs.

Jclgodale3

Ok...update with no resolution. I put one old tire/wheel setup on the right rear and one new tire/wheel setup on the left rear. Drove it. Same reaction...lurching, hopping under load. Swapped the other new tire/wheel setup on the left rear and got the same reaction so I don't believe it is a damaged wheel or imbalanced tire unless I got lucky? and both rear wheels are damaged or unbalanced.

BigBlok502

WAG here (Wild Azz Guess) The tires are asymmetric, are they mounted on the rims correctly? In other words, are the outsides of the tires facing the outside of the rims?

Jclgodale3

yes sir..confirmed

jaredtxrx

Have you gotten the new TPMS sensors calibrated to the car yet? My guess is you with either have to tow the car to get this done or find someone that can come to you.

Do you still have the DIC message about Active Handling? If so have you tried to pull any codes?

Jclgodale3

hopefully programming the TPMS tonight.
never had a DIC message on “active handling” so not sure what your referring too

Jclgodale3

So...I️ put some hub centric 4mm spacers on the rear since there was a very close proximity to the left rear cooling duct. Drove it, then drove it hard and not a hint of a problem like before. Feeling good, I️ put it up and discussed with a fellow gearhead and we were both perplexed that “that” was the problem. Took it for another spin and the same damn problem came back. I’m more convinced this is a computer or electronics issue now...but what???

Jclgodale3

all 4 TPMS are now married to the car...no difference. Same problem

jaredtxrx

Man that sucks. I've really got nothing else to offer up except hoping that it gets figured out.

Just a couple quick things (can't remember what all you have tried).

Try making sure traction control is off to see what happens.

Put the rear tires in the air and (this is super dangerous) and put the car in gear and see if you can see if there is any binding going on or if the rear calipers are freaking out.

Ben101er

I had mine "road force balanced" by a GM dealer, twice, and they told me the first time, there was nothing wrong. The 2nd time, they told me it was a wheel issue. I took it to an independent tire dealer that I had used for years, and they balanced them the old fashion way, on a spin balancer, and sure enough, they were just not balanced properly. Ran smooth after that. The guy at the GM dealer just had not been trained properly on the equipment.