Staggered generally means different diameter tired e.g. 19 in front and 18 in back.cant imagine why just changing width 20would. Cause issues Whic is less than an inch wouldaffect anything.now if you put different diameter tires on.or different height it might cause issues
That was my confusion too. I took it to the dealership and the guy putting them on was pretty clueless telling me that was the diameter size not the width of tread. They also tried to tell me that I would need to tune it for the new size tire setup lol
Staggered doesn't mean different wheel diameters, it typically refers to different wheel widths (ie. 19x10 fronts and 19x11 rears) and resulting differences in tire sizes (ie. 255mm F vs 275mm R). He also changed the actual diameter of his tires going from 255 to 275 while remaining with a 40 sidewall profile.
Typically it's on the order of ~3% where shifting starts to get clunky.
Don't need a tune per se, but resetting it via Forscan may help with the clunkiness by correcting speedometer. From what I've read, the transmission may be trying to command a shift at specific mph, but if the tires are spinning at a different mph (due to differences in tire diameter from factory), then this may lead to shifting issues/clunkiness.
There wasn’t a problem with shifty since I have a manual. It was strictly the front end wanted to dart side to side and was really unstable. Also the TC would kick on doing 50mph or more around exit and on ramps.
Ah in that case, ignore everything I said lol
Alignment and balancing was all squared away. My friend runs the exact same staggered setup that I was trying to put on and hers runs just fine, although it came like that from factory so there’s the difference. I just can’t wrap my mind around how I wouldn’t be able to do the same thing and have the dealership program it just as hers is setup. Just think it was a case of someone not knowing what they were doing. Hence the mechanic trying to tell me that the 275 was diameter and not tread width.
I presume a mechanic knows basic tire principles so he may have been trying to say that switching to the 275 from 255 tread width actually changes the diameter if the side profile remains the same as the 2nd number (40 in your case, 275/40/19) is a percentage of the tread width and not an absolute number. So, going from 255/40/19 to 275/40/19 changes both your tread width and your tire diameter by 0.7" as stated by previous poster.
How wide are your wheels? Information I've found indicates that they could be 9" or only 8.5".
I’m unsure of wheel width
Do you have a base or pp model GT?
I’m currently running the stock size 255/40/19 on all four wheels and they’re Pirelli Zero Neros. The tires I tried putting on the back were the continental DWS ExtremeContacts and leaving the Pirellis on the front.
