Towing with 35's and 4.56's or 4.88's

[JAngeli]

I'm in the same boat. Running 35's with 3.73's and the NV4500 tranny. Pulling a 6000 lb 28' travel trailer and I feel it going up hills. By the sounds of it, may go 4.88's since it has the O/D. Eventually wouldn't might getting a 454 Vortec in it. Truck is used only when needed and not a DD.

 

[grantxurismo]

4.56 all the way
4.10 is close to stock with 35s, just a little taller, (currently what Im running)
I think 4.30 would be the sweet spot but thats a ford ratoi if im not mistaken

 

[clubber]

I've got 4.56's but with 31's. It's great for towing but a little short for running empty. The 4.88's would be about the same gearing with 35's as 4.56's with 31's so I'd say 4.88 for towing duty.

 

[Bricksack]

4.56 with 36x15.50's . Towed a 93 k1500 on 38's on a 1200lb military 20' car trailer at 65mph just fine. Also have a 454 and lifted 6"

Sent from my SGH-T989 using Tapatalk 2

 

[97SilveradoHD]

4.56 with 36x15.50's . Towed a 93 k1500 on 38's on a 1200lb military 20' car trailer at 65mph just fine. Also have a 454 and lifted 6"

Sent from my SGH-T989 using Tapatalk 2

looking to regear mine to either 4.56 or 4.88. curious what rpm you're running on the highway, say 70 mph.

 

[88GMCtruck]

IIRC mine is about 2,200 at 60

Sent from TBI 454 HTC Droid DNA

 

[JScott23]

i think you'd be happy with 4:56.

4:88 might be a little much..


4:88's at 70 MPH would be 3200 RPM with 35" Tires

4:56's at 70 MPH would be 3000 RPM with 35" Tires

4:10's at 70 MPH would be 2700 RPM with 35" Tires


I would always put it into the gear ratio calculators before would even consider re-gearing

 

[Vortec Lover]

could you run 3:73's through your calculator? just curious....

 

[JScott23]

3.73's would be 2500 rpm with 35" tires..

one other thing worth noting is this calculator uses a 1.1 final drive ratio... i think his NV4500 should have .73?

I'll try and re-figure... 4L80E's are at .75


I'll post all of it here give me a few!

 

[JScott23]

Sorry guys our trannys aren't 1.1 ratio's!!! Ignore above... I calculated this at .74 final ratio. 4L80E's end at .75 and the NV4500's are .73.

3.73's w/ 35" Tires @ 70 MPH = 1800 RPM
4:10's w/ 35" Tires @ 70 MPH = 2000 RPM
4:56's w/ 35" Tires @ 70 MPH = 2200 RPM
4:88's w/ 35" Tires @ 70 MPH = 2400 RPM

that's the correct information given our transmissions final drive ratio's.. The .73 and .75 only make like 50 RPM difference at most so i didn't bother calculating the difference's between the two. Now realize if you put stock tires back on it'll be rapping out at like 3k so that would be bad..