2000 Dodge Cummins with 3.55 gears

The auto's do much better with 4:10's towing. Your problem is not going to be going up hills if you get out of Florida, it is coming down. the OEM setup does not lock the torque converter going down hills and it just free wheels, requiring you to use the service brakes to slow it down. I have a 2001.5 4x4 auto that I spent a bunch of bucks on to beef up the tranny, keep in locked up and an exhaust brake.

If the tranny has not been beefed up and it has 165K on the clock, do not add power at this point.

1. Gauges
2. Custom Tranny
3. Torque Converter lockup box.
4. Exhaust Brake
5. 4:10 gears if you are going to see America.

If you are going to stay in Florida where the bridge in Jacksonville is the highest point in the state, then you will be ok for a while. Note however the the 47RE tranny was the weak link with the Cummins up front.

Over the years I have done all the tricks to mine: Gauges, injectors, tranny, exhaust brake, different turbo, chip, after market lift pump, steering brace, 3rd gen track bar(4x4), 4 low kit(4x4), more caster(4x4) and big exhaust(for cooling, does no increase HP) and Amsoil in the tranny and diffs!

I get in the high 11's or low 12's overall towing a 12.4K 5th wheel. 15+ around town and 19-20MPG on the road empty.

Chris

Highly recommend a steering stabilizer for the steering box. It's a frame to frame bolt on that stops the steering box from flexing on the frame. The increase I steering ability is nice.

I had a '01 2500 Dodge/Cummins 3.54 235/460 with the 47RE. One sick puppy in od which is a .69 OD. Ran the truck in 3rd gear. My neighbor had a same '00 one ton DRW 235/460 with the 5 speed manual and 3.54 gears. He had no problems pulling any weight.

Your going to have to pull with it and see if you like the 3.54 gears. I sure didn't.

I changed my 98 12V 2500 4X4 auto from 3:55 to 3:73 and it made a big difference. With your setup I would not go to 4:10.

When you get down to about 1,700 rpm drop it into 3rd back out of the throttle and cruise up the 6% grades at 55 or so.

If you want better mileage and performance install a set of Bosch 275 RV injectors. You will be amazed. They come in your same engine in motorhomes.

To answer your question the 3:55 will be fine.

352 wrote:
I have a new to me 2000 Dodge 5.9 Cummins 2 wheel drive with 3.55 gears. I have a 12,000 LB. loaded 5er. I went from a F-350 with 4.10 gears which was never a factor to what I have now. Will the 3.55 gears be a problem in the mountains?

Well I have the 01 in my signature, with a DS Power Puck, 5 speed and 3.55 gears. My 5er weighs right about 11,000# and I need to drop to 4th on steep grades. I can reach between 50 and 60 while climbing these grades. Weighed the last trip out an at state weigh station 1/2 tank of fuel we were right at 18,500# GCVW.
On the flats I need to use cruise in 5th, or be very careful to keep my speed below 60 (Oregon most roads have a 55 speed limit) less steep hills I can climb easily in 5th.

You have a ways to go to find any real hills, there a couple of grades in the Appalachian Mountains that will challenge you, but you will need to travel a ways to find them. Worst case change the gears for a set of 4.10's

I have a 4 speed auto. I am the 3rd owner. To my knowledge it has not had anything done to the tranny. 164,000 on the clock.

You will probably drop into 3rd on the hills.

Dad has an '01 with a 6spd, 4wd, and Edge-EZ chip with 3.55 gears. With my 7k TH never out of 6th, 20k combined would pull it down and go to 5th on the steep, 28k combined it would flat land 6th just fine but would need to go to 5th earlier.

I don't ever remember needing to go to 4th unless we had to make a turn.

The lack of gears sucks (I've got a 4spd auto in my '05). Wish I had the 6spd but oh well. You will see 3rd on climbs, and 4th everywhere else. I doubt you will have any issues.

Does the new2U Dodge have an automatic?
If so I don't believe you'll have much trouble pulling hills.

Just curious if yer truck has an auto has it been replaced\rebuilt previously?