4.56 or 4.88

[brian3180]

stock tires,no lift.5.7 lwb,qc,1500,2wd...what would be the best ratio for towing?i would rather over do it. 4.56 or 4.88

 

[Redtruck-VA]

Brian, my thought is if you need a 4:88 to pull your highway load you probably need a 2500 or bigger truck. 4:56 is one of the best mods you can do on your truck ad will make it very drivable. good luck

 

[AF_Hemi]

^^^yep.

 

[03MopaRamman]

^^^For Sure, You'll be Impressed!

 

[Bad Habit]

double yup....4.56 ftmfw

 

[Ram Man]

At 70 mph on 33s (stock size tire) and 4.88s your rpms would be around 2400....
4.56s at 70 your rpms are a little more gas friendly around 2200..

OR you could buy 4.56s and trade them for my 3.55s and at 70 mph youd be at around 1700

 

[4XLGATOR]

I gotta move 4.56's up in the order on my mod wish list.

 

[brian3180]

im running 1800 rpms at 70 all stock. has any one ran into problems when installing.

 

[KGBIGCOUNTRY]

1800 at 70 sounds like 3.55s are in there now. Just take it to a shop that knows what they are doing and break them in the correct way.

 

[Marx]

yep 4.56 ftw unless your drag racing with the trailer lol

 

[Hemiguy0302]

I gotta move 4.56's up in the order on my mod wish list.

With the diesel I would not bother unless you plan on running 40's or bigger

 

[4X HEMI]

It you have stock tires, no lift and a 2 wheel drive what do you want 4.56's for? What gears do you have in it now? A lot of dealers ordered trucks back in 03 with 3.92's, I believe most of the 2wd's were 3.55's though.

Unless your planning on running some big tires, you should be good to go. I would have loved to have the 4.88's but when I did my gear swap they were not available yet for my truck.

 

[brian3180]

if i do have 3.55 should i go with 4.56 and not 4.10?

 

[Redtruck-VA]

if i do have 3.55 should i go with 4.56 and not 4.10?

If you are running 33" tires and towing I would say 4:56. I have 30.5" tires on my street truck and wish I had gone to 4:56 instead of 4:10's. Your choice.....

 

[onebadbee]

4.56s at 75 is around 2500 rpms with 28 inch tall tires NOT FUN

but with 30 inch or taller tires you should be fine

4.56s are nice but forget your 80 mph days

 

[brian3180]

just got my build sheet from the dealer.i do have 3.55 gears and a 545rfe trans.my tire size are 265/70/17= 30" tires. not real worried about going 90mph just a little better pulling.so i hope 4.56 will be a good upgrade.

 

[STOUTE]

I just did 4.56 and love them

 

[4XLGATOR]

With the diesel I would not bother unless you plan on running 40's or bigger

You know, I never thought about it in regard to the engine....just along the lines of the tire. My truck really does fine on the interstate and towing. At approximately 75mph on the interstate I'm until 2k rpm.

So good...more money for other mods.

 

[brian3180]

has anyone done a lsd diff,gears,and trans shift kit at same time?and has anyone ran into any problems as far as computer problems between the gears and shift kit?i had a guy at ammco tell me it would cause some problems with the computer.havnt gone into details with him cause he is not doing the work.

 

[Redtruck-VA]

has anyone done a lsd diff,gears,and trans shift kit at same time?and has anyone ran into any problems as far as computer problems between the gears and shift kit?i had a guy at ammco tell me it would cause some problems with the computer.havnt gone into details with him cause he is not doing the work.

Brian, my advice is don't use that guy as he doesn't know what he is talking about. I did gears followed by a couple days with the TC install on my 03. PCM is not effected by these changes. I also have the TMR mod and line Pressure boost resistor installed without issue. However I did installed a DSP tuner and it caused anti-lock warnings and has what the dealer says electronically locked my PCM so I can't update the PCM. You might read the 03 thread that is posted. Good luck...