2nd Gen Non-Engine/Transmission Axle gearing for towing

[Road Dog]

I'm looking at getting a small (10K GVW) 5th wheel and have a Diesel/4x4/RE-47/3.54 drivetrain. According to my trailer guide the GCWR is 16,000 and going to 4.10 gears bumps that to 19,000. Living in BC it's all about mountain driving so I already spend a lot of time in third and second with a slide-in camper. I'm rarely over 60mph.

Looking around the Internet, some drivers claim they do fine with 3.54 gears. Do they really? Should I consider re-gearing?

 

[petersonj]

Don't know the status of your transmission, but if the transmission was built with a triple-disc converter lock-up, a low stall speed torque converter, and lock-up available in all forward gears, I think that transmission in front of 4.10 gears would be a good combination - especially if an exhaust brake was added.

You would have great pulling power, hold-back power, and the tall overdrive would keep the engine rpm's down some. A low stall speed converter will keep engine rpm's down and make much better use of available low rpm engine torque when the torque converter is unlocked.

- John

 

[BarryG]

As John said 4:10s would be good. I had an 01, I had built it up to about 400hp and 900tq. It did have the 3:54 gears and a good built transmission. It was actually built in BC by Bill Kondolay of DTT transmissions way back when. I live in Colorado and had no problem towing our 10k 5th wheel in the mountains. However the fiver only got used a few times a year and I normally drove the truck about 30+k miles a year so a lot of empty or should say non towing driving. My other trailer at the time was only a 3500lb utility trailer which was never a problem. While I never had any issues with pulling the fiver 4:10s would have been nicer for sure on those long grades here. I had thought about regearing but never did as I just couldn't justify the cost of doing both front and rear axles for the amount of heavier towing I did at the time where it would be beneficial. If I were you I might see how it goes before I plunked down $3-4k to regear. Now if you can regear yourself obviously the cost would be much less. You would know after one or two trips. If your truck is stock power then I would probably lean even more towards 4:10s.

 

[BigPapa]

As mentioned, you'd be better off spending the re-gear money on the transmission. Triple-disc TC and a valve body minimum.

 

[GAmes]

About a million miles of towing with my 3.54 gears, the majority west of the Mississippi and a lot in B.C. I used to own a triple slide 5er that weighed close to 13,000 pounds. I towed it across the Rockies and visited Banff National Park on the way to Alaska. Stock tire size is 215/85R16 and I stayed with that size. I sincerely doubt a 10,000 pound trailer would require the cost of regearing, but if you are sporting oversize tires you might want to consider going down a size or two. I have also read that B.C. is the only place where the authorities care about manufacturer's ratings.

 

[Ozymandias]

What tire size are you running?

 

[Road Dog]

What tire size are you running?

The stock 235/85R16.