I tow a 13K lb Fifth Wheel in the mountains (I live in Colorado) and I was wondering if anyone has lowered their gears? I had 4:10's in my Ford PSD that I traded for my GMC. I loved the gears. Much easier to get the load moving and now with the 6 speed I can hardly ever use 6th. It is too tall in the hills so I am stuck in 5th all the time. I was thinking that lower gears would allow me yo use the taller gear and maybe even get a little better millage towing. My truck is in my sig. It is pretty much stock except for a mild Edge tow tuner and gauges.

def wanna do the ppe air box mod, block the egr, pvc reroute, and get 4 inch turbo back exhaust in addition to help keep your EGT's lower.

4:10's would be a good move to me, esp if your towing most of the time.

I can't see how regearing will help your mileage. If you lower your rears and the transmission will finally get to 6th, you will be putting more stress on those taller gears. You will still be running the same RPM for the most part, but now when you are unloaded you will be running much higher when you are at highway speeds. Now your highway mileage will end up dropping.

If you went up in tire size I could see how it might be a benefit, but it would take a pretty good jump in size to need the taller gears.

With all this being said, I just pulled a 40 GN w/ three jeeps/buggies up through CO running about 30k lbs and I thought it did just fine w/ the 3.73s. Yes, it stayed in 4th or 5th on some of the big hills, but the transmission stayed cool and the engine seemed to like the RPMs it was having to turn to keep the load moving.

I agree on gsxr's suggestions. Those will help tremendously.

Hey guys I need some help here. I gotta an 06 Chevy 2500 HD series w/alison transmission. We thought the fuel filter may have been bad, but we changed it. The truck is not smoking or missing, but it just dont wann run over 2000 rpm. Can anywone tell me what we could do here on the side of the road.

my 06 dmax 2500 w/ alison tran wont run over 2000 rpms. We have changed fuel filters, engine oil and air filters. Nothing has helped or made a difference. It just seems to max out at 2000 right now. I need your help.

post a new thread brandynatruck.

and to the original poster, i dont think you want 4.10s to get it in 6th. notice if your in tow/haul mode that it doesnt go into 6th gear. at least mine doesnt. 6th is like an economy gear

Challenger,

4.10's will actually make you run a higher RPM and you will loose highway mileage. It also will let 6th hold longer but that is also creeping your exhaust temps up. If it were me I would leave well enough alone. 4th or 5th going up the hills is fine. You make it up those hills so then there is no beef. That gear change would buy a lot of camping trips and fuel.

post a new thread brandynatruck.

and to the original poster, i dont think you want 4.10s to get it in 6th. notice if your in tow/haul mode that it doesnt go into 6th gear. at least mine doesnt. 6th is like an economy gear

Mine will go into 6th w/ tow/haul on. It might not stay there very long w/ a big load and any hills, but it will get there. :D

Challenger,

4.10's will actually make you run a higher RPM and you will loose highway mileage. It also will let 6th hold longer but that is also creeping your exhaust temps up. If it were me I would leave well enough alone. 4th or 5th going up the hills is fine. You make it up those hills so then there is no beef. That gear change would buy a lot of camping trips and fuel.

I agree, let the transmission do it's job and put the money you would spend on gears into other more beneficial mods.

Moved to Drivetrain.

I'm running 4.10 gears in my 08 dually, however I'm running 33s on 22s for wheels/tires too. I'm very glad I made the switch for towing purposes. It will not help your mileage at all on a stock truck, in fact, probably hurt it a bit. It will give you more low end power to help get the loads moving. You are running stock sized tires correct? I tow a 30' flatbed with my big show truck or a tractor on it quite often and it does just great with the 4.10s. 4.10s wouldn't hurt your truck by any means, just don't think they would give you the mileage gain you're wanting.

Us guys with earlier model trucks tow in 5th gear all the time, we don't have the 6th gear. That 5th gear you have is an overdrive. I don't think you will loose much by just towing in 5th gear.
I don't see any differance between using 5th gear with your present gears and 4.10's and using 6th gear. Sure the 4.10's will get you moving better, but you'll loose economy running empty.