which gears would you go with in my case ??

[Turboedsupe]

07 Tahoe with 3.42 in right now. Its got a 2/4 drop on 24x10 wheels and 305/35 tires. The rims are 3 piece so there a little lighter then your typical wheels. I tow a single axle 8x12 with a 1400lb RZR most the time. On occasion I'll do a 7x20 tandem axle and 2 RZR's. The problem I ran into last night was I couldn't stay at 60+mph in 4th. I was having to stay in 3rd most the time which is wasting gas and putting tear and wear on her. So 4.10 or 4.56? I was just over 1800 rpm at 70mph in 4th. This is a daily but don't get on the freeway too often.

 

[socaltahoe]

i would do a 4.10's

 

[LRob]

4.10

 

[Big Buttons]

4.10s if you drive at freeway speeds, 4.56 if you really want low end power

 

[ccapehartusarmyINF.(ret)]

okay first off your maybe just over half the towing capacity of the vehicle wich is like 6500lbs with a 3.42 and the second thing is you should be using tow/haul mode wich i believe wont allow the tranny to shift into OD or 4th unless you reach 65 and if you cant stay at 60 mph towing not much more then half the vehicles towing capacity you shouldnd be in OD anyways that puts much more strain and wear on the tranny so burning more gas in third is alot cheaper then a new tranny( do you live in the ALPs or something). 3.73s is plenty if you thing 3rd gear with a 3.42 wastes gas a 4.10 axle will make burn gass faster then you can put it in the tank and god help you witha 4.56
and your mileage wont get much better when your not towing

 

[TowGMC]

Something's wrong. 1700 at 70 in 4th gear and it won't tow? Friends use their '07 & '08 Tahoes to pull 4500 lb race car trailers all the time and they all use 3rd gear. 4th is too far off the torque curve to work well. You need to be in the 2400-2800 rpm range to pull any major weight. Going from 3.42 to 4.10 will get you to about 2200, and I bet you still have to drop to 3rd. Putting in 4.56 gears will put you at 2400 in 4th, which is probably about what your run now in 3rd.

You say running in 3rd is added wear and tear. I would suggest that lugging an engine and transmission at 1800 in 4th trying to pull a heavy trailer is worse, especially since the trans is probably downshifting and unlocking the torque converter all the time. That's added heat and friction.