I pull a small fifth wheel and my truck has the 3.55 rear end. I was wondering which would be better to get, the Smarty, upgrade to 4.10 or maybe both.
Any thought would be welcome.

Thanks,
Alan

 

Smarty, a 4.10 turns up too much rpm and kill your mgp. your truck makes enough torque for what your pulling.

 

4.10's + interstate= not fun....that's a lot of rpm's at 75mph.
My work pickup is '96 cummins with 4.10's, it's nice in town, but are not good for the highway, I hardly ever drive faster than maybe 65mph with that truck.

 

I agree 100%. Unless you tow really heavy loads, you won't like the 4.10 gears, the RPMs are way too high. I have 4.10s on my 01, and I hate them.

 

4.10's in my 03, hate them as well. 70 mph at 2200 and goes up fast from there. Kind of limits high speed cruising . Changing them in the plan.

 

i have 4:10's and i live around alot of mountains and yes they are kind of a pain on the freeway but when i hit the mountains i laugh at you guy's that don't have them. read the sig.

 

i also have 4.10's but i also have 325/50/R22 Toyo Open Country A/T's on my truck.. so that offsets my gears a bit.. so its not too bad on the highway.. i still see 14-15 MPG at 80 MPH on the highway.. thats with the edge box off.. and smarty on 8.

 

My freeway miles are pretty good with 4:10's. I usually lick along at around 70+/- and get around 17mpg. A mixture of freeway/town gets me right around 15mpg.

I tow a boat/trailer combo (12k) and in stock form my truck had some issues on the hills. Piece of cake now!

 

Before USLD, I had gotten as high as 22mpg with my 4:10's at 72mph on cruise control. A couple weeks ago with USLD pulling 2 place aluminium trailer with 2 snowmobiles and gear at 78-80mph I got aprox. 15mpg. Not bad in my book considering my old 360 gasser would have been around 8-10 mpg.
P.S. my truck has 285's and the speedo was corrected and all figures are hand calculated.

 

Thanks for the help guys. I'll go with Smarty first and see what happens.

Alan

 

Wow, what's the secret? Was your truck on the back of a flatbed tow truck?