Aftermarket wheels without re-flash

TMCINTOSH11

MEMBER
2006 DODGE CHARGER
5.7L
V8
2WD
AUTOMATIC
164,255 MILES

Hi, I recently got my transmission rebuilt and the shop advertised me to check into re-flashing the TCM to the wheel specifications to keep the transmission from wearing down faster, I did some research and it turns out that in order to re-flash it I would have to buy an aftermarket tuner tool like diablosport which are on the expensive side since the dealership isn't able to do it for me. Then someone said as long as the current tire height is similar to the original factory tire height then it won't need re-flashed, so I got the original factory tire size from the dealership and compared it to the current size online and it looks like the current size is.68" higher than the factory height. A lot of performance shops said that it'll be fine that way without re-flashing, even the dealerships. So I just want a good opinion on this before I start driving it again, current size is 265/35ZR22, factory size is 225/60R18, will it be okay without doing any adjustments or reprogramming? I didn't know with bigger rims if the weight of the rims would be an issue also, thanks in advance!

Images (Click to make bigger)

5 Replies

ASEMASTER6371

MECHANIC
52,797 POSTS

Good evening,

There is no way that is good.

You have changed the size a lot.

The aspect ratio, or the distance between the rim and the top of the tire is a lot different.

You need someone to check the speedometer for accuracy first. The roll speed will be different and you need to find out how much different it s. Then you will need to have the ECM adjusted to that wheel speed.

Roy

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

Monday, August 3rd, 2020 AT 3:49 PM

TMCINTOSH11

MEMBER
176 POSTS

Hi Roy,

Yeah, I bought the car with these installed already. I did a lot of checking around with performance shops before I started driving it again. I asked the dealership about it and they said they couldn't do it and I needed an aftermarket tuner like diablosport, those are awfully expensive just to adjust the tire size input, they do offer a ton of performance tweaks too, but I just want to drive it worry free. It wasn't easy paying $3,538.00 to rebuild the transmission and I tried to make sure it wasn't going to hurt it again, a lot of shops said only the tire height really mattered. If it was close to the original factory tire size then I was told it was okay, but what I was looking at the tire circumference. It's definitely more by 2.14" even though the height is only.68". If you think I should wait until I get this fixed before I drive it again then I will. I checked the speedometer and it's slightly off, at 60 mph my gps says I'm going 61 maybe 62 mph, thanks for your input Roy!

Was this

answer

helpful?

Yes

No

Wednesday, August 5th, 2020 AT 4:41 PM

ASEMASTER6371

MECHANIC
52,797 POSTS

I think you can drive it now but not forever. You can do it temporarily until you can get it set up correctly.

Roy

Was this

answer

helpful?

Yes

No

Wednesday, August 5th, 2020 AT 4:46 PM

TMCINTOSH11

MEMBER
176 POSTS

I appreciate your advice! I been wanting stock rims on it with a little wider tire. I hope width doesn't effect it much. Anyway thanks a lot for your help Roy. Here's a picture of it with the current wheels on it.

Image (Click to make bigger)