jhook

Hey there new to the forum and I have a question for my first thread. I am looking at new trucks and am planning on also buying a camping trailer maybe 6-7000# and only going to use 4-5 times a year maybe other towing as well but would 3.55 be good or 3.73 also is it worth it to get the rear lock out I dont off road but I live in the north so winters can get bad from time to time. I think I'd have to get the 3.73 if I get the rear lock out and dont know how much gas mileage would suffer? Any thoughts would be appreciated or life experiences that would pertain.

Goober

I'm guessing that 7k is the dry weight on your trailer?
If so, you probably going to be towing 8-9k?
Definitely go with factory tow pkg.
If you don't want dumbo mirrors, a lot of folks are opting for the regular tow pkg, plus adding the factory brake controller.
(what I have)
Either rear will pull that load, of course 3.73 will be happier doing it at a small cost in mpg.
I always loved 3.73, but did not like the locker, I ended up with a EB 3.55 ls.
EB torque pulls that 3.55 with no trouble, I suppose your engine choice would play into the equation.
Also, while you might pull 4 times a year, how far do you go?

If it were me making the choice:
If 5.0, probably 3.73.
If EB or 6.2 prob 3.55 ls, unless you really like a locker...
(P.S. Locker only works in 4wd under 25mph. Otherwise your stability control handles things.
Folks say it feels alot like a LS rear.)

Also keep in mind: while these trucks can pull up to 11k, 9k is a pretty healthy load.
Don't know your experience level, just to let you know.

zap

Putting a mechanical locker in my 02 was the best thing I ever did to the truck. You have to be careful with a locker in an auto in cold weather...most people give it too much gas when sitting on ice. Its not like a standard where you can just let the clutch out to get off the ice slowly. I have 3.55 but for your intents a 3.73 would be best. 4.10 probably is too low for what you want. Mileage depends on a couple of thing when your geared like that.

I have a 06 Mega Cab with 4.10 gears and a Cummins 5.9L straight 6 and it is just broken in (104K miles). The original tires got roughly 24 mpg with the truck. Upgraded to 35" tires and its now pulling 28+ mpg on the highway (empty of course). That does counter act the 4.10 a little, but you are more or less fooling the truck into thinking its running a higher gear set while technically increasing the torque at the rear wheels (torque is a force by distance measurement, bigger tires, bigger distance) and still have the available torque to pull 10.5 tons.

You have to look at some of the little things and weigh it against your purposes for the vehicle. Cause such a little thing such as a half rotation of the engine from the gearing can really affect how you pull and what kind of mileage you get.