Different 5 ton transfer cases?

[Unforgiven]

Is there only one type of 5 ton transfer case?

Just curious. I need a TC capable of handling the torque from a Cummins 8.3L.

Do the regular sprag type 5 ton cases split the power 50/50 or is it torque sensing, only engaging the front when the rears slip?

Thanks.

 

[73m819]

ONLY engaging when the rear slips.

You can install a 900 tc, this is air shift with full time front drive when engaged,

Also you can install a tc from a 6x6 civi mixer, these are air shift for H/L and front drive.

 

[Wildchild467]

ONLY engaging when the rear slips.

You can install a 900 tc, this is air shift with full time front drive when engaged,

Also you can install a tc from a 6x6 civi mixer, these are air shift for H/L and front drive.

You said it will make it "full time front drive" are you saying it will be just like a deuce then? the term "Full time" with the transfer case in jeeps mean you can run it on hard road, but part time is where both outputs of the t-case are locked together (like the deuce). I think you mean the 900 series t-case would lock both outputs of the T-case together, correct? I like the 800 series 5 tons, but would think an air shift t-case would be a lot nicer. All respect to guys that like sprags, i just like the idea of kicking it in 6 wheel when i want it to. Thats just my preference.

 

[73m819]

You said it will make it "full time front drive" are you saying it will be just like a deuce then? the term "Full time" with the transfer case in jeeps mean you can run it on hard road, but part time is where both outputs of the t-case are locked together (like the deuce). I think you mean the 900 series t-case would lock both outputs of the T-case together, correct? I like the 800 series 5 tons, but would think an air shift t-case would be a lot nicer. All respect to guys that like sprags, i just like the idea of kicking it in 6 wheel when i want it to. Thats just my preference.

FULL time, yes like a deuce air shift, the front and rear is locked together, though running on hard road in 6x6 would be HARD on the drive
.

I believe that The full time 4x4 in jeeps and other full time 4x4s tc has a differential or some other mechanisms that smoothes out the torque to both axles, other wise things will get broke with unmatched toque

Also I have seen differentials in civi big truck TCs, in some mixers and in some 6x6 and 8x8 oil field pole trucks

 

[Ridgerunner]

In my opinion, any tranfercase that you can select at your own descretion, 2-wheel drive or 4-wheel drive, would be a 'Part-time" transfer case, not a "Full-time" transfercase.

Example: Full size American truck T-cases, shift patterns

New Process 205 "Part-time" Transfercase

High Range-4x4
High Range-2x4
Netural
Low Range-4x4



New Process 203 "Full-time" transfercase

High Range-Lock
High Range
Netural
Low Range
Low Range-Lock

 

[73m819]

Ok,I see your point, where you CAN'T shift out of 4x4, In that case I am talking about PART time, I guess my terminology could be confusing, I'm thinking when you shift the air shift tc into front drive it becomes full time front drive until shifted out manually, as compared to a sprag set up that shifts automatically as needed do to spin and the over running clutch. ( a part time front drive due to the in/out action of the sprag action)

 

[mudguppy]

...
New Process 205 "Part-time" Transfercase

High Range-4x4
High Range-2x4
Netural
Low Range-4x4



New Process 203 "Full-time" transfercase

High Range-Lock
High Range
Netural
Low Range
Low Range-Lock

these are two perfect examples of 'Part-time' vs 'Full-time' transfers.

'Full-time' transfer cases have some sort of provision for speed differentiation and/or torque management between the two outputs. 'Part-time' cases do not.

the air-shift transfer cases are 'Part-time' cases because they lock the front and rear outputs together and do not permit speed or toque differentiation. i've never thought about it, but i guess one could consider a sprag-type case as a 'Full-time' transfer because of the over-running directional ability.

but i don't know if i'd classify it that way, though.

 

[gringeltaube]

.......................... a part time front drive due to the in/out action of the sprag action)

Ron, I liked that definition for a sprag...!

.... but I have to agree with mudguppy as well...LOL

G.

 

[73m819]

High Range-Lock[/B]
High Range
Netural
Low Range
Low Range-Lock[/QUOTE]
What is the difference of LOCK and non LOCK

 

[mudguppy]

High Range-Lock
High Range
Netural
Low Range
Low Range-Lock...

What is the difference of LOCK and non LOCK

the NP203 is a neat animal - it has a center differential to act as a 'Full-time' transfer case, but has a 'Lock' option. this 'Lock' couples the front/rear outputs together just as a 'Part-time' transfer. you use this when you're offroad in slippery situations.

in all actuality, this 'Lock' is necessary; otherwise, power could be transmitted freely to slipping wheels front or rear and not get you anywhere.

HMMWVs use a similar transfer.

 

[Unforgiven]

So, if I am understanding these large transfer cases:

800 series are sprag
900 series are air-engaged-front like the Oshkosh HEMTT TC's

Either one should be able to handle the 600-1000 ft-lbs produced by the 8.3C Cummins.

The HEMTT is just an Oshkosh55000 like found in many civilian heavy trucks, right?

 

[Derrickl112]

the m939a2's have the 8.3 cummins in them. so the transfercases can obviously handle it..

 

[Squirt-Truck]

We identify the sprag case as "on demand" because no torque is sent to the front axle, unlike either the full time, until traction demands the front to pull. The sprag case has many advantages in severe off road application in addition to the hard surface use.

To address the original question, the 5-ton case will handle the torque from an 8.3 after all it handles the torque from the N14 just fine.

 

[Unforgiven]

Please forgive my ignorance. What are the advantages of the on-demand sprag? Logic would suggest that 100% engagement of all axles at all times would be more beneficial.