2.5 ton rockwell how much can it take?

[Ryan123]

yeah that seems like that can get pretty expensive. Also the gears are still pretty low even in the 5 tons. Just read an article on the 2.5 ton t case and people are still using them in monster trucks with 60 inch tires and big power. That being said I am not too worried about it anymore.

 

[gringeltaube]

Here ill do the math for you. The gears cost 1200$ each so that's 3600 bucks not cheap I know but its better than a brownie box (hacked in).

Here is the math

2100 RPM divided by .63 trans OD =3333.33 divided by 4.90 axle ratio= 680.27 times 10.55 rolling circumference of my 43 inch tires at 96 percent =7176.87 feet per minute times 60 minutes = 430612.24 feet per hour divided by 5280 feet per mile =81.55 MPH

that being said I DO NOT WANT TO RUN THAT FAST however without the gears you get 59 mph. I would like to run 65 MPH at a lower RPM for better fuel consumption and not have to have the motor pegged out.

This style sounds all so familiar..... it's been a long time we didn't hear from this guy... we sure had some fun here...!


G.

 

[gimpyrobb]

WOW G! Had to bring THAT back up...

 

[Ryan123]

This style sounds all so familiar..... it's been a long time we didn't hear from this guy... we sure had some fun here...!


G.

I dont really care who you "trolled" it is all to common on SS tbh. But back to a more serious note on with the initial question.

 

[steve6x6x6]

Here ill do the math for you. The gears cost 1200$ each so that's 3600 bucks not cheap I know but its better than a brownie box (hacked in).

Here is the math

2100 RPM divided by .63 trans OD =3333.33 divided by 4.90 axle ratio= 680.27 times 10.55 rolling circumference of my 43 inch tires at 96 percent =7176.87 feet per minute times 60 minutes = 430612.24 feet per hour divided by 5280 feet per mile =81.55 MPH

that being said I DO NOT WANT TO RUN THAT FAST however without the gears you get 59 mph. I would like to run 65 MPH at a lower RPM for better fuel consumption and not have to have the motor pegged out.

It will cost you more than $3,600.00 , shipping + bearings + seals + labor. 65 mph X 43" tire X 4.90 ratio X 37% OD = 1,667 rpm?

 

[Ryan123]

It will cost you more than $3,600.00 , shipping + bearings + seals + labor. 65 mph X 43" tire X 4.90 ratio X 37% OD = 1,667 rpm?

well yeah I suppose you are right on that but I dont think it will be 5500 hehe. Yes 1667 RPM sounds about right. The 6v92 I think (i would have to go look) makes peak torque at 1500 rpm

 

[steve6x6x6]

5 ton axles with 6.44 and 43" tire and just the 37% OD at 65 mph = 2,171 rpm, save a lot of money. OR 14.00x20 tires 65 mph at 1,894 rpm.

 

[Ryan123]

correction 1300 rpm is peak torque.

 

[Ryan123]

Yeah I did the math on that just a bit ago. Its a tough call... 5 tons would be nice... still though thats pushing that 92 running like that for hours on end while on the highway. IF ONLY IT WAS A 6:1 GRR. The marine guys run the 6v92's at 2300 RPM I think I might talk to one of my contacts to see how long they run them like that to see if they hold up or not. I really do like the 5 ton Idea though!

 

[steve6x6x6]

You should ride with me in my A3 at 60 mph with 2,800 rpm's for 500 miles one way. OR 5 ton with 16.00x20 = 1,746 rpm

 

[Ryan123]

how is it? lol

 

[w3azel]

5 ton third members fit into 2.5tons?

I was referring to an ouverson violator kit that changes over to 2" 47 spline shafts. Rear is $1700 front goes from $2550 to $4050 plus machine work. Just on option to think about if you start breaking stuff.

 

[Ryan123]

I was referring to an ouverson violator kit that changes over to 2" 47 spline shafts. Rear is $1700 front goes from $2550 to $4050 plus machine work. Just on option to think about if you start breaking stuff.

man that is steep... I did see those kits. I was thinking of doing the 4.9 gears with the girdle kits to stiffen the 2.5 tons up a bit

 

[NDT]

I'll chime in. My deuce tractor runs 185 hp LDS and I used to gross 50,000 GCWR and run 55 mph. The Rockwells would just about be glowing after hours on end. The axles can handle significant hp and torque in spurts, but the heat buildup is what kills them for OTR use with big power and weight.

 

[Ryan123]

I'll chime in. My deuce tractor runs 185 hp LDS and I used to gross 50,000 GCWR and run 55 mph. The Rockwells would just about be glowing after hours on end. The axles can handle significant hp and torque in spurts, but the heat buildup is what kills them for OTR use with big power and weight.

so would say 6-7 hours be considered to long I suppose?

 

[porkysplace]

Just go buy a 6x6 from a power company and put a deuce cab and front end on it .

 

[Ryan123]

Just go buy a 6x6 from a power company and put a deuce cab and front end on it .

I already have a deuce I dont need more vehicles lol

 

[rustystud]

I'll chime in. My deuce tractor runs 185 hp LDS and I used to gross 50,000 GCWR and run 55 mph. The Rockwells would just about be glowing after hours on end. The axles can handle significant hp and torque in spurts, but the heat buildup is what kills them for OTR use with big power and weight.

NDT you got that right ! On our busses we have differential coolers since they use gear reductions in the hubs. That really can get hot ! Our busses are also speced out at 35mph as the average speed. I used to rebuild double reductions single speed and double reduction two speed units a lot. These trucks they where in never went over 40mph. In fact most never left the woods they worked in. All over the road riggs differentials only use a single gear set, never a double like our rockwells.

 

[Ryan123]

did you have lube pumps for them to run diff coolers or how was that set up?

 

[Jeepsinker]

If you want to go the 5 ton axle route I can get you some with the old hydraulic brakes on them.