[bmk10]

Since I have no experience with gears other than 3.73's I can't make up my damn mind. I'm running 35's on a 6in lift. The majority of my driving is 35-55/60mph. I don't want 4.56's bc I want more get up and go out of the truck and highway driving doesn't happen often in this vehicle.
Is anyone running 4.88's or 5.13's with 35's? When you're cruising and downshift to pass someone does it send the rpms through the roof? I guess that is my biggest concern. Along with not putting too much stress on the rest of my drive train seeing that it is about to click 170k.
I'd really like to order these gears soon so if some of you guys can help me make a decision it would be much appreciated!
-Brad
By the way I have a 1500 with a 4l60e trans.
EDIT: If anyone has a link to a gear ratio calculator that is actually ACCURATE and will tell me my rpm through each gear that'd be sweet! The link in the sticky isn't working.

 

[beckmand78]

http://www.gmfullsize.com/forum/showthread.php?t=240146

 

[00silvyON]

Since I have no experience with gears other than 3.73's I can't make up my damn mind. I'm running 35's on a 6in lift. The majority of my driving is 35-55/60mph. I don't want 4.56's bc I want more get up and go out of the truck and highway driving doesn't happen often in this vehicle.
Is anyone running 4.88's or 5.13's with 35's? When you're cruising and downshift to pass someone does it send the rpms through the roof? I guess that is my biggest concern. Along with not putting too much stress on the rest of my drive train seeing that it is about to click 170k.
I'd really like to order these gears soon so if some of you guys can help me make a decision it would be much appreciated!
-Brad
By the way I have a 1500 with a 4l60e trans.
EDIT: If anyone has a link to a gear ratio calculator that is actually ACCURATE and will tell me my rpm through each gear that'd be sweet! The link in the sticky isn't working.

These 2 links is all you need to know. Enter the numbers into the calculator. This is almost bang on perfect from real world.

http://en.wikipedia.org/wiki/GM_4L60-E_transmission

http://www.angelfire.com/fl/procrastination/rear.html

 

[bmk10]

http://www.gmfullsize.com/forum/showthread.php?t=240146

I read the sticky dude. The link doesn't work in it. I want a calculator

 

[bmk10]

These 2 links is all you need to know. Enter the numbers into the calculator. This is almost bang on perfect from real world.

http://en.wikipedia.org/wiki/GM_4L60-E_transmission

http://www.angelfire.com/fl/procrastination/rear.html

Thanks a lot! can you verify how accurate this thing is though because it's telling me at 76MPH I will be only at 2600RPMS with 5.13's….I feel like that isn't right. Won't the rpms be higher?

 

[00silvyON]

Thanks a lot! can you verify how accurate this thing is though because it's telling me at 76MPH I will be only at 2600RPMS with 5.13's….I feel like that isn't right. Won't the rpms be higher?

I tested it at 3 different RPM's (1300, 2600, 4000 in 3rd) versus the specs on my truck, this thing is damn near perfect! was around +/- 2 mph what my GPS says in the truck

 

[beckmand78]

I read the sticky dude. The link doesn't work in it. I want a calculator

Touché. My bad. I suppose I'll throw my opinion in here- Just do 4.56s. I did and had plenty of power and the truck didnt scream on the highway. If you want fast, get a cam and tune.

 

[bmk10]

I tested it at 3 different RPM's (1300, 2600, 4000 in 3rd) versus the specs on my truck, this thing is damn near perfect! was around +/- 2 mph what my GPS says in the truck

Interesting. Thanks man!

 

[bmk10]

Touché. My bad. I suppose I'll throw my opinion in here- Just do 4.56s. I did and had plenty of power and the truck didnt scream on the highway. If you want fast, get a cam and tune.

Haha no prob. What'd you run with the 4.56's, 35s I'm guessing? And yea a cam and tune is next on the list but i need to build the budget first lol.

 

[beckmand78]

Haha no prob. What'd you run with the 4.56's, 35s I'm guessing? And yea a cam and tune is next on the list but i need to build the budget first lol.

yeah 35s. There's a reason 4.56's and 35's are so popular. They just work.

 

[bmk10]

do you know what your rpm's are at 70 on the highway? Im assuming you have the same trans as me

 

[NuckenFuts]

I just installed 5.13's this weekend with 33" and almost wish I went 5.38. At 70 im at around 2600 RPM with my 4L60E. With 35's I would for sure go at least 5.13. Trust me you will not regret it. I was getting 10 MPG with my 3.73 with my 5.3 and now 6.0. I feel the engine was always lugging. I would bet that I will get better gas mileage now. 4:56 is to small of a change to even make it worth your time. Alot of people told me I was stupid for going 5.13 and everyone that has rode in my truck now has said wow This isn't bad at all and they all love the power.

If you want real gas mileage numbers I can PM you the number when I get it.

 

[brucebruce45]

I just installed 5.13's this weekend with 33" and almost wish I went 5.38. At 70 im at around 2600 RPM with my 4L60E. With 35's I would for sure go at least 5.13. Trust me you will not regret it. I was getting 10 MPG with my 3.73 with my 5.3 and now 6.0. I feel the engine was always lugging. I would bet that I will get better gas mileage now. 4:56 is to small of a change to even make it worth your time. Alot of people told me I was stupid for going 5.13 and everyone that has rode in my truck now has said wow This isn't bad at all and they all love the power.

If you want real gas mileage numbers I can PM you the number when I get it.

This

 

[bmk10]

I just installed 5.13's this weekend with 33" and almost wish I went 5.38. At 70 im at around 2600 RPM with my 4L60E. With 35's I would for sure go at least 5.13. Trust me you will not regret it. I was getting 10 MPG with my 3.73 with my 5.3 and now 6.0. I feel the engine was always lugging. I would bet that I will get better gas mileage now. 4:56 is to small of a change to even make it worth your time. Alot of people told me I was stupid for going 5.13 and everyone that has rode in my truck now has said wow This isn't bad at all and they all love the power.

If you want real gas mileage numbers I can PM you the number when I get it.

I'm sold! 5.13's it is. :favorites37:
Yes please PM me the numbers if you don't mind. Thanks for the input man, exactly what I needed to hear!