Transfer Case/Power Question

[Steelreaper80]

So, hopefully in about 2 months I will send my truck in to have it professionally turned up. I am just not brave enough to do it. I have a mowing contract in Terre Haute Indiana and will drop it off at Scheid Diesel and have them do it along with changing the timing to 16 degrees and installing a pyro and boost gauge. My question is why is the transfer case the main limiter of the power that these trucks are capable of? Just for comparison, I pulled up the specs of the new Ram 3500 with the 6.7 HO Cummins and they are 410 HP and 1000 FT LBS of torque. Our engines have a larger displacement and in theory, can produce much more power. Everything on these trucks is massive when compared to a 1 ton truck. The axles, driveline, brakes, etc. How can an MT654CR Allison not handle what a modern but much lighter duty transmission can? I will have them tune it to around 300 HP and about 900-1000 FT LBS of torque. I know over that everyone says that things will break above that but my question is....why? Is it the weight of the truck coupled with the power in comparison of a 1 ton or is it something else? Just curious.

 

[simp5782]

600 series transmissions are rated up to 275hp and 700 ft lbs. That is probably a conservative rating of 10 or 20% under spec. I mean it will handle the power if you are using your head along with your foot.

I never got more than 30k miles with the Allison's in my 5 ton. They just burned up.

 

[74M35A2]

It is easier to get power using a modern 4 valve EFI engine with VGT and charge air cooler vs an old 2 valve mechanical engine with just a simple yet hot aftercooler. The EFI can spray 5 separate pulses per combustion event, to reduce noise, emissions, increase power, cold startability, etc...

Also modern transmissions have an engine torque reduction request circuit for every shift. The engine torque is brought way down for a short time during the gear change, then restored once the shift is completed. This adds huge life margin and power capability to transmissions today.

Longevity will depend on your load. Empty truck and no trailer? Should last a long time.

Keep us posted. You should get some good gains out of it that really increase the fun level of driving it.

 

[Steelreaper80]

I pull a M322 trailer with anywhere from 15k-24K on the trailer regionally. I put around 10-15K miles on the truck annually.

 

[ericp351]

I'd also consider the type of oil and how often you change oil and filters when predicting reliability.

 

[Steelreaper80]

I'd also consider the type of oil and how often you change oil and filters when predicting reliability.

Shell Rotella and either Fleetguard or Wix filters all changed at 10,000 miles as per the Cummins manual.

 

[Steelreaper80]

I'd also consider the type of oil and how often you change oil and filters when predicting reliability.

Shell Rotella and either Fleetguard or Wix filters all changed at 10,000 miles as per the Cummins manual.