: going from 17' to 20's



taylor2000
03-22-13, 03:44 PM
Ok newbie here. I belong too alot of forums but now we can add another.I do alot of postings, questions and help when I can. So now I need your help. Momma bears cadillac has from factory the 17' aluminum wheels. She wants to go to some aftermarket 20's. Ok besides the TPS being a hurdle what about the transmission, traction control anti lock brakes? The cadillac not mine but some came out with the 20's. So If we purchase tires that are the same size as some factory esculades do we still have to reprogram our esculade to one. 2006 cadillac esculade

the cadillac man
03-22-13, 04:39 PM
Ok newbie here. I belong too alot of forums but now we can add another.I do alot of postings, questions and help when I can. So now I need your help. Momma bears cadillac has from factory the 17' aluminum wheels. She wants to go to some aftermarket 20's. Ok besides the TPS being a hurdle what about the transmission, traction control anti lock brakes? The cadillac not mine but some came out with the 20's. So If we purchase tires that are the same size as some factory esculades do we still have to reprogram our esculade to one. 2006 cadillac esculade

As long as the overall size is the same it won't hurt nothing except the ride due to the heavier rims

taylor2000
03-22-13, 04:53 PM
so what you are saying is. 265 70 r17 which are mine. and going to other factory size 275 55 r20 is ok. Are these the same height? Is this why? didnt figure the truck would know. rim sized changed if the tire compensated it.

the cadillac man
03-22-13, 05:19 PM
so what you are saying is. 265 70 r17 which are mine. and going to other factory size 275 55 r20 is ok. Are these the same height? Is this why? didnt figure the truck would know. rim sized changed if the tire compensated it.

Place them side by side that will tell you if there is a difference(the main reason I said about the overall diameter is the speedometer and odometer will be off due to the size difference if not the same overall)

wake
03-22-13, 06:18 PM
so what you are saying is. 265 70 r17 which are mine. and going to other factory size 275 55 r20 is ok. Are these the same height? Is this why? didnt figure the truck would know. rim sized changed if the tire compensated it.

Check this site out, it has a comparison calculator.

http://www.paspeedo.com/calculator.htm

taylor2000
03-22-13, 06:41 PM
Check this site out, it has a comparison calculator.

http://www.paspeedo.com/calculator.htm ok just so this doesnt get drawn all out ill explain. The
dealership told me that the transmission is programmed for the 17 inch tires and not the 20's/ I will have to buy a program from gm and have them release it to the dealership. If they will he said. And then they will have to reprogram ours with the 20's. They said the transmission wont shift right and can throw all kinds of codes. Other treads state that traction control can kick on at anytime if you change size of tire. 80 dollars for the program and another 180 to install it. so 260 to reprogram for the 20's in which esculades came out with.

the cadillac man
03-22-13, 07:02 PM
ok just so this doesnt get drawn all out ill explain. The
dealership told me that the transmission is programmed for the 17 inch tires and not the 20's/ I will have to buy a program from gm and have them release it to the dealership. If they will he said. And then they will have to reprogram ours with the 20's. They said the transmission wont shift right and can throw all kinds of codes. Other treads state that traction control can kick on at anytime if you change size of tire. 80 dollars for the program and another 180 to install it. so 260 to reprogram for the 20's in which esculades came out with.

You can for go all that trouble if the new tires and times are the same outside diameter (both being 35 inch for example)
A easy way is the put the old tries and rims next to the new ones if the new one are a little bit taller it won't hurt nothing(I am running larger tires on the stock rims and no codes or issues with the tranny)

wesyder
03-22-13, 07:49 PM
ok just so this doesnt get drawn all out ill explain. The
dealership told me that the transmission is programmed for the 17 inch tires and not the 20's/ I will have to buy a program from gm and have them release it to the dealership. If they will he said. And then they will have to reprogram ours with the 20's. They said the transmission wont shift right and can throw all kinds of codes. Other treads state that traction control can kick on at anytime if you change size of tire. 80 dollars for the program and another 180 to install it. so 260 to reprogram for the 20's in which esculades came out with.

Fyi my 24 inch wheels with tires were the same diameter round as my stock 17's, no issues, no programming, no codes.... Any size wheel you go with should be ok the amount the speedo will be off you will not notice unless you go with too small of a wheel which wont fit or too big of a wheel with a huge off road tire

wake
03-22-13, 10:46 PM
ok just so this doesnt get drawn all out ill explain. The
dealership told me that the transmission is programmed for the 17 inch tires and not the 20's/ I will have to buy a program from gm and have them release it to the dealership. If they will he said. And then they will have to reprogram ours with the 20's. They said the transmission wont shift right and can throw all kinds of codes. Other treads state that traction control can kick on at anytime if you change size of tire. 80 dollars for the program and another 180 to install it. so 260 to reprogram for the 20's in which esculades came out with.

I'd find a new dealership, this one sounds like they're trying to make some money off of you.

Your car's computer doesn't care if you have 20" 17", 18", etc wheels on it as long as the total rotational diameter is the same or close to the same. The only ill effects you'd see with a slightly undersized or oversized tire is speedometer error or slight fuel economy differences if you under or oversize.

You're not going to affect the driveability unless you do something drastic like put way undersized or oversized tires on it or different diameter tires between front and rear or side to side.

Needing special programming is suspect as well. I have the same Tech II that the dealership uses and I can select the tire size right from the tool without any special programming or interface with GM TIS. It has built in the various tire/wheel sizes that the Escalade came with no, 'special' program needed.

the cadillac man
03-22-13, 10:50 PM
I'd find a new dealership, this one sounds like they're trying to make some money off of you.

Your car's computer doesn't care if you have 20" 17", 18", etc wheels on it as long as the total rotational diameter is the same or close to the same. The only ill effects you'd see with a slightly undersized or oversized tire is speedometer error or slight fuel economy differences if you under or oversize.

You're not going to affect the driveability unless you do something drastic like put way undersized or oversized tires on it or different diameter tires between front and rear or side to side.

Needing special programming is suspect as well. I have the same Tech II that the dealership uses and I can select the tire size right from the tool without any special programming or interface with GM TIS. It has built in the various tire/wheel sizes that the Escalade came with no, 'special' program needed.

Couldn't agree more

sprink60
03-23-13, 09:46 AM
I went from 17" to factory 2012 22" and the static loaded radius was exactly the same...other than a TPM swap no adjustment required. Some one is throwing you a line of crap.

taylor2000
04-03-13, 03:16 PM
got them insalled and look great. drives a little different. but all is good