justinmc978

wanting to get 275-40r17 front and 275-40r18 rear for a slightly aggressive stance, but I'm afraid since the r18 tire is ~1" wider in diameter (and thusly the tires will rotate at different speeds) that this might trigger the 'low trac' light and cause my brakes to act funny. anyone who runs drag radials have any experience with this? does the 'low trac' only come on when the rears are spinning faster than the fronts? thanks ya'll.

edit: I have no TCS, if you do/don't have it please say so.

JohnnyBz28

iTrader: (12)

It's not the width that will cause issues, it's the 1" difference in height that causes ABS issues.

MidknyteRacer

Negative on all accounts bro. I've ran 275/35/18 Nitto 555R's & 275/30/19 NT's on the rear of my 97,98, (both ran DR's) and current 2001 Camaro SS (NT's) with no issues at all. And honestly its nothing a simple tune couldn't fix, but trust me dude you'll be fine.

JohnnyBz28

iTrader: (12)

I ran a 1" taller tire and had ABS/Low Traction issues.

82cetuner

iTrader: (9)

a 35/18 and a 30/19 are not that different in height

JohnnyBz28

iTrader: (12)

ha I just noticed what tire size he had put in his post.


OP the two tire sizes you posted have a 1" height difference.........do a search and you will see that this will cause the ABS/LowTrac light to pop on and the ABS to act up.

ANTICOP RAM AIR

iTrader: (7)

I have that setup on my 99 ws6... I have no problems problems but I have no traction control either

justinmc978

Thanks, that's what I'm trying to find out, did it affect your braking at all?


Also, I've been searching every LS1 related forum for days, there are no topics on this anywhere, if you can't tell I dont post much, so when I do it's something I really can't find. If you can find another thread related to this it would be appreciated.

justinmc978

you mean TCS or you had the 'low trac' indicator tuned out? they are two different things...

justinmc978

and he is right, there is only a ~.08" difference between those two, now if you ran a 275/35/18 front & 275/35/19 rear, then you would have a considerable difference.

infamouzlsx

I have 2453518 in front and 2854518 in rear and I get the abs light on

ANTICOP RAM AIR

iTrader: (7)

I didnt have it tuned out, i have no TCS, or the button.. I didnt know if that made a difference. I know my rear differential is different because of it... 4 channel = TCS+ ABS. 3 channel = ABS only. The 4 channels have 2 sensors and two reluctor rings, each behind the rotor. The 3 channel has a single reluctor/sensor on the carrier inside the diff. Just thought it was a good thing to know since there is a bit of a difference. Hope this helps. Honestly, there should be a lot of guys one here running my setup, its very common. Hell, half the corvette rims on here are 17,18 combos and lots of guys run the same profile which when done so with different diameters, results in a different rolling diameter of each tire.

I think my info is correct... check me before quoting me.. lol IVE BEEN DRINKING!!!

justinmc978

Affect the drivability at all? or is it just a light? and do you have TCS?

I don't have TCS either, but all of our cars still have the 'low trac' light and ABS, just trying to figure out if

a) having significantly larger diameter tires in the rear will trigger this system (I think we have established that it will)

b) does having TCS affect this?

c) does the system being triggered have an effect on drivability, or is it just a dummy light?

ANTICOP RAM AIR

iTrader: (7)

thats what Im saying, I have no TCS and I get NO LIGHT.. some that do get a light may have a different rear than you and I do...

Are you guys who get the light running a 3 channel or 4 channel rear end? I think that may be the difference.. maybe I can say that I have run this same setup on every single one of my Fbodys and Ive had 7... but none of them had TCS and I have never gotten the ABS light

justinmc978

okay, NOW I see why you are talking about the 3/4 channel rear end

so like he said, you guys who are getting the light, do you have TCS?

ANTICOP RAM AIR

iTrader: (7)

As far as drivability, you would probably lose the ABS function since they wont pulse like theyre supposed to.. you will still have brakes, just no ABS...

infamouzlsx

I get those lights the check gages is due to being low on gas lol
It only happens when I go over 60mph for longer then 2 minute. then as soon as I turn my car off, and turn it on again lights go off. And my abs is not working due to the tire differrence

justinmc978

I've decided to just go 17" same size all around, cheaper and won't have to deal with this. my current car is A4, and I didn't realize that even if I didn't have ABS problems that having bigger tires would make my shifting goofy. I'll just wait until I get my M6 WS6/Z06 to do this.

thanks for everyones input.

JohnnyBz28

iTrader: (12)

Yes it did affect my braking. It causes the ABS to kick in when it isn't necessary and can cause you to crash at a high rate of speed.

MidknyteRacer

Well it seems you need to go with a smaller height tire for your larger wheel. I've never gone above 35 with any of my aftermarket wheel/tire setups, and I guess my preference paid off, my stock 17's are 275/40's so obviously no issue, but maybe that's why I have never had any issues because I like low profile tires. ABS works, no inop, when its to slick and I lose traction the low traction indicator kicks in just fine and bogs me out, my traction control still stays on with no issues and works fine, turns on and off like usual.