3.73's Or 4.10's

[animalguy]

Other than watching driveshaft/tire revs is there an easy way to tell if I have 3.73 or 4.10's? Is there an axle tag or a digit in the VIN? The truck is new to me.

[jaybyrd]

There should be some RPO codes on a sticker in the glovebox but I don't remember which code is which. Do a search for the codes, there's a link somewhere to a huge pdf file listing all the codes.

[breecher_7]

List your VIN, i can pull the invoice for it......

[seamonster]

3:73 is GT4

4:10 is GT5 I think!

[pwall]

GU2 = 2.73 Ratio

GU4 = 3.08 Ratio

GU5 = 3.23 Ratio

GU6 = 3.42 Ratio

GT4 = 3.73 Ratio

GT5 = 4.10 Ratio

[kaferman]

Thanks for the code info! I have 3.23 in my 06 5.3 ext. cab. Couple of questions.

 

The sticker on the truck states 3.23, towing capacity of 6100 pounds, the owners manual states 6900 with the 3.23 and 5.3 in ext cab.

 

My current Travel trailer loaded is 4500 pounds, and when we hit the hills, it is constently shifting, and I want to reduce that. Fuel mileage is not a concern, but when not loaded, I use on highway around 70-80mph, so a 4.10 might be a bit too tall.

 

I am thinking of upgrading my travel trailer to a 5000 (dry weight), ~6500 loaded travel trailer. I also am thinking og changin to a 3.73. According to the manual, 3.73 is 7900 pound rating. Should I subtract the 800 pounds as the sticker does? Why would it be different?

 

If the gear is changed to 3.73, do any of the electronics need to be modified?

 

Thanks!

[svensk]

Thanks for the code info! I have 3.23 in my 06 5.3 ext. cab. Couple of questions.

 

The sticker on the truck states 3.23, towing capacity of 6100 pounds, the owners manual states 6900 with the 3.23 and 5.3 in ext cab.

 

My current Travel trailer loaded is 4500 pounds, and when we hit the hills, it is constently shifting, and I want to reduce that. Fuel mileage is not a concern, but when not loaded, I use on highway around 70-80mph, so a 4.10 might be a bit too tall.

 

I am thinking of upgrading my travel trailer to a 5000 (dry weight), ~6500 loaded travel trailer. I also am thinking og changin to a 3.73. According to the manual, 3.73 is 7900 pound rating. Should I subtract the 800 pounds as the sticker does? Why would it be different?

 

If the gear is changed to 3.73, do any of the electronics need to be modified?

 

Thanks!

4.10 would be a "shorter" gear, and yes you would like it.

Is this a 4x4? If no, gear changes would be somewhat more simple.

Yes, you would need your PCM calibrated for your new gears because shift points, ABS might all be off.

I would then get a custom PCM tune from someone like Wait4me.

If you upgraded your gears, which I would do if you get a heavier trailer your truck will be like a rocket ship compared to 3.23's. I'm talking almost a full second better 0-60, which translated into jerking that trailer around a lot easier.

[kaferman]

Good info! The truck is only 2WD, and a local shop quoted me ~800 bucks for the changeout. I will confirm that includes the PCM mod as well.

 

What all would the Wat4Me tune do, what do they cost, etc?

[svensk]

Good info! The truck is only 2WD, and a local shop quoted me ~800 bucks for the changeout. I will confirm that includes the PCM mod as well.

 

What all would the Wat4Me tune do, what do they cost, etc?

A wait4me would give you some more HP, firmer shifts, less power robbing torque management, and cost 158 bucks for a new PCM shipped to you.

[C & A s Dad]

You will see my truck in my sig and I am pulling a 6500lb camper (fully loaded) with it. I am very happy with the 4.10s and would go so far as to say that I would not want to pull this much weight with my truck with anything less than the 4.10s or possibly 3.73s.

 

Even with the 4.10s I pull in 3rd and keep it at 65 or below on the Interstate and 55 or below on 2 lane roads. This keeps the 5.3 in it's "sweet spot".