Got New 08 Sierra Denali

[007Poke]

Came with 18" wheels and I swapped for the 20s, rmps at 70 approximately 1700. I would swear that the Denali I test drove with 20s from the factory ran around 1900 at 70. What should the rpms be? I thinking maybe the dealership did not change tire size in the computer.

[dietz4ibanez]

We need PICTURES!!!

[dietz4ibanez]

Oh and welcome to the site!

[Darkanion]

Came with 18" wheels and I swapped for the 20s, rmps at 70 approximately 1700. I would swear that the Denali I test drove with 20s from the factory ran around 1900 at 70. What should the rpms be? I thinking maybe the dealership did not change tire size in the computer.

80 in my '07 SD (w/ 20's), is just a hair less than 2k RPM. So, 1700 @ 70 sounds about right.

[dietz4ibanez]

Came with 18" wheels and I swapped for the 20s, rmps at 70 approximately 1700. I would swear that the Denali I test drove with 20s from the factory ran around 1900 at 70. What should the rpms be? I thinking maybe the dealership did not change tire size in the computer.

80 in my '07 SD (w/ 20's), is just a hair less than 2k RPM. So, 1700 @ 70 sounds about right.

 

 

 

Wow didnt know that thing of your would go that fast!

[Darkanion]

Wow didnt know that thing of your would go that fast!

Well, it's not usually loaded down with fake 'leveling kits' like some of you guys do!

[dietz4ibanez]

haha

[007Poke]

Came with 18" wheels and I swapped for the 20s, rmps at 70 approximately 1700. I would swear that the Denali I test drove with 20s from the factory ran around 1900 at 70. What should the rpms be? I thinking maybe the dealership did not change tire size in the computer.

80 in my '07 SD (w/ 20's), is just a hair less than 2k RPM. So, 1700 @ 70 sounds about right.

 

 

Thanks. I will check it out tomorrow. Maybe it just felt like I was going 70 when I did my test drive.

[007Poke]

We need PICTURES!!!

 

I will take some, posting them will be the trick.

 

Thanks for the welcome.

[Darkanion]

Thanks. I will check it out tomorrow. Maybe it just felt like I was going 70 when I did my test drive.

Yeah, these things move along pretty good.. I found out about the artificially low speed limiter by accident, one day, going from one of our locations to another. It sure didn't "feel" like I was going almost 100 mph!

[kdogg]

Came with 18" wheels and I swapped for the 20s, rmps at 70 approximately 1700. I would swear that the Denali I test drove with 20s from the factory ran around 1900 at 70. What should the rpms be? I thinking maybe the dealership did not change tire size in the computer.

80 in my '07 SD (w/ 20's), is just a hair less than 2k RPM. So, 1700 @ 70 sounds about right.

 

 

Thanks. I will check it out tomorrow. Maybe it just felt like I was going 70 when I did my test drive.

 

Just my two cents, but it's not just the wheel size but tire size that can change the ratio. If you have a Garmin or other gps device, and if not borrow one and drive at 70 according to your speedometer, then see what the gps says. The gps's aren't perfect but damn close. Then atleast you can see if it is off. If it is it will be noticable. I know mine is. I just need to find the time to change it, but also I have 2 sets of wheels and tires one for winter and one for summer. The winter tires are taller so this will always change.

 

[Darkanion]

Just my two cents, but it's not just the wheel size but tire size that can change the ratio. If you have a Garmin or other gps device, and if not borrow one and drive at 70 according to your speedometer, then see what the gps says. The gps's aren't perfect but damn close. Then atleast you can see if it is off. If it is it will be noticable. I know mine is. I just need to find the time to change it, but also I have 2 sets of wheels and tires one for winter and one for summer. The winter tires are taller so this will always change.

 

If he sticks with the stock tire sizes, it shouldn't throw his speedometer off by much.

[ChrisNJ]

You can do a simple test on a highway. Keep it at 60mph constant, and time yourself between mile markers. should be 60 seconds per mile. If lower, say 57 seconds, you are going around 63mph.