: 26" rims cause tranny problems?



THE MECHANiC
03-31-08, 06:27 PM
does anyone know if having 26's cause problems to the transmission? is their something to prevent this?

KillerBlackbird
03-31-08, 07:57 PM
I don't see why it would...your stock brakes might wear out quicker. I've had 24's on my 07 Sierra Denali for a few thousand miles with no issues. A good way to look at it is; the vehicle was meant to pull how many thousand pounds with a trailer? So 400lbs or so of rotating mass I dont think would be a problem.

SWRidin
03-31-08, 08:08 PM
I heard a rumor about 26s cause this problem. I think you would need to upgrade to 4.10 gears.

When I first heard the new Lades were running 3.42 gears I was shocked. I see how thier trying to squeeze out more fuel economy.

Like lifted trucks with bigger wheel/tire combo's than stock require upgrading the gears.

Otherwise they don't have the leverage to get the torque to turn those big wheels.
Sure you'll turn them but you'll be sluggish and slow off the line.
Upgrade the gears and you'll put the power down.
Downside is worse gas mileage, at higher speeds 4.10 will cause your RPMs to be higher.

Heavy cast wheels are alot to ask 3.42 gears to turn.

Expensive 3 piece wheels are supposedly lighter and will probably help. But ofcourse are more expensive.

I'd run 3 piece forged 26's on 3.73 gears. If I had the money.

For now I'll stick to 24's on 3.42s.

hcvone
04-01-08, 09:07 AM
Anytime you change things that a car/truck was designed/built for there will be issues, putting on larger wheels and tires are not bad, UNLESS your replacements are much heavier, as many aftermarket non forged wheels are, even adding 5 lbs of extra weight will cause your brakes to wear more quickly, will cause a lot more stress on your transmission, transfer case and front and rear diffs, as well as your front suspension parts. Many aftermarket tires and wheels weigh 25 lbs more that stock. I know when I was having wheels made for my different cars and SUV's weight was the most important thing, also strength was very important to me, I would not drive on cast aftermarket wheels after seening all the failures on larger case wheels, and broken wheels from pot holes. My 24's are 4 lbs lighter with tires than the stock 22's with tires.

ewill3rd
04-01-08, 09:13 AM
If the rolling circumference of the wheel/tire is larger than the factory combo you will have all sorts of issues.
The computer won't know how fast the vehicle is really going and shift points will be really screwed up.
What is the prize for having the biggest rims? :lol:

hcvone
04-01-08, 10:49 AM
I have a customer getting 30's, will post pixs when he stops by, I would think it will look wierd, but I will wait until I see it in person

THE MECHANiC
04-01-08, 12:57 PM
i never had issues with my 24's but any suggestions on solutions to get my transmission fixed to take the stress of the 26's??? as for the prize for biggest rims ..no prize just competitive nature in men i guess anything you can do i can do better..oh and people who can AFFORD to get $6000 plus rims on a $70K truck can AFFORD to get other upgrades to prevent other issues im sure LOL

hcvone
04-01-08, 01:19 PM
i never had issues with my 24's but any suggestions on solutions to get my transmission fixed to take the stress of the 26's??? as for the prize for biggest rims ..no prize just competitive nature in men i guess anything you can do i can do better..oh and people who can AFFORD to get $6000 plus rims on a $70K truck can AFFORD to get other upgrades to prevent other issues im sure LOL

Most owners do not even get their fluids changed :(

91sonomast
04-01-08, 01:34 PM
haha exactly, they will spend 10's of thousands of dollars on making it blingbling-a-reffic, but wont properly maintain it, then come crying and bitching to you when something breaks as soon as his warranty is up and expecting u to fix it. sorry dude, u didnt maintain ur vehicle, ur problem.
as far as what to do to create less stress, there are TWO options......well three MAYBE, money cant buy everything.
1. Buy EXPENSIVE 10-15k wheels and tires that are super light
2. enjoy the 22's
3. IF someone offers a performance rebuilt transmission, buy it and put it in and have ur drivetrain warranty voided.
idk how most dealers operate, but if u come in having drivetrain issues with anything bigger than a 24, we blackflag ur warranty. call it shitty, call wrong, call it what u will, but heavy ass wheels put alot more strain on a vehicle than a trailer. rolling mass is hard on a vehicle.
we dont blackflag the warranty if they are high end lightweight wheels. but i have pulled off wheels before that weighed 98lbs. EACH..........I WAS PISSED, to say the least.

mattroberts123
04-01-08, 01:37 PM
I've had cast 26s on my past 2 tahoes (2002 & 2005) then cast 24s on my H2 sut (2006) and now forged 26s again on my new ext (2008)

Comparing the weight and quality.. along with the ease of balancing the combo, I too would recommend forged wheels. They are a lot more money, but if you want to be a big dog and roll with big wheels, spend the extra money and get the best.

Never had any issues of any kind with any of the vehicles (aside from slight rubbing in the fenders)

I think as long as you don't abuse the vehicle, and pay attention to the regularly scheduled maintenance, you should not have any issues.

I would recommend always reprogramming the vehicle to the changed tire/wheel size.

THE MECHANiC
04-01-08, 04:19 PM
would the dealer be able to reprogram the vehicle to 26's or where would i be able to get this done.

SWRidin
04-01-08, 04:21 PM
You would have to buy a programmer. Search the forum for those recommended. Superchips or Predator or others will allow you to program in your new tire height.

Unlikely the dealer will be able to help you but possible. Give them a call.

THE MECHANiC
04-01-08, 04:28 PM
can dealer reprogram vehicle?

THE MECHANiC
04-01-08, 04:38 PM
ok thanks

ewill3rd
04-01-08, 04:48 PM
GM will only let us do calibrations for "approved" tire sizes.

hcvone
04-01-08, 04:59 PM
Bill cleared that up, you will need an aftermarket programmer