took factory wheels off 17" and put 20s on and vibrated when i hit the brakes

**RidemHard04** · 03-07-2009, 06:52 PM

i have a 07 classic 4 door..got 20inch wheels off a regular cab...when u hit the brakes they shake so bad u almost wreck its bad bad...so i thought it was just warped rotors....negatory captain...took the 20s off...put the 17 stockers on...was fine so the brakes were perfect...i put em on the regular cab and they didnt shake...my gross weight is 7000 an ex cab is 6400 or 6700 i cant remember..do yall think where it weighed more that might have something to do with it cause i dont know what it would of been...nobody does it just doesnt make sense other than the wheels not rated for the weight of a 4 door even tho they dont weight that much more???? any help appreciated thanks taker easy or taker however u can geter haha

**heavy chevy** · 03-07-2009, 07:58 PM

Have the wheels rotated and balanced You will also have to recalibrate the spedo for the 20s that may have been some of the problem. IF you decide you wana sell those 17s give me a pm i might be interested in getting em from ya. Ohh make sure the tires are not directional if they are directional and not facing the right way they will shake.

**benhartholt** · 03-07-2009, 10:53 PM

Did your overall wheel size change? If so it could be your ABS brakes kicking in.. I have that with my bigger tires so I just take out the ABS fuse and it's fine. I actually almost hit someone one time because my wheels were ABS-ing everytime I slowed down so it would let me brake.. haha. anyways good luck!

**RidemHard04** · 03-08-2009, 12:53 AM

no im not selling the 17s there my factory wheels i put back on..i put new cooper zeon ltz 275-55-20 and they didnt vibrate on my regular cab but they went insane on my 4 door..it just doesnt make any sense..im from charleston wv and nobody has a clue why they are smooth on a reg cab and when u hit brakes they go crazy on 4 door...i removed the abs before i put my 17s back on..im speechless..if you have a reg cab cuz i know they dont shake on my reg cab im sellin em..i paid 700 for tires and the wheels are SSC proformance style 78 on the sears website..i have pics on my myspace if you wanna add me www.myspace.com/robpenn is the link...thanks a bunch

**RidemHard04** · 03-08-2009, 12:55 AM

i forgot to put for the first guy that replied...i did balance them..i watched them do it myself the tires dont have maybe 100 miles on em...the wheels were 204 a peice and tires were 700...ill sell em to someone with a reg cab since they dont shake on those for some odd reason for around 1 grand..let me know

**Jimmiee** · 03-08-2009, 11:06 AM

Originally Posted by benhartholt

Did your overall wheel size change? If so it could be your ABS brakes kicking in.. I have that with my bigger tires so I just take out the ABS fuse and it's fine. I actually almost hit someone one time because my wheels were ABS-ing everytime I slowed down so it would let me brake.. haha. anyways good luck!

I would think twice about disabling my ABS system. If you were to get into an accident and there were injuries the first thing that happens is they investigate the vehicles involved. The second thing you will see is a big lawsuit! JMO

**hunky** · 03-08-2009, 04:48 PM

Are you using the right lug nuts with the 20's. I think they are diffrent.

**lawson4450** · 03-08-2009, 10:32 PM

yeah check the lugs and i believe the wheels are hubcentric if they put them on a normal balancer instead of thru the lug balancer they will not balance now matter what i went thru this(altough that was aftermarket wheels). if the rims are done thru a normal balancer if you take of and put it back on the balancer it will not balance right.

**benhartholt** · 03-10-2009, 10:50 AM

Originally Posted by Jimmiee

I would think twice about disabling my ABS system. If you were to get into an accident and there were injuries the first thing that happens is they investigate the vehicles involved. The second thing you will see is a big lawsuit! JMO

I took off the ABS system in all of my trucks! I find I have better control braking with no ABS.. But I guess it's good for people who have trouble braking in slippery weather.

**tlperry68** · 03-10-2009, 12:04 PM

The factory puts on two copper keepers over the lug nuts to help with installing the rotor. These keepers are two per wheel, they are smashed in when the wheel is set with an impact gun. Did you pull them off when you replaced the wheels. I was told by a trusted GM mechanic that those can make aftermarket wheels wobble.