M1088 M1078 axle difference

[Lmtv772]

What is the difference between M1078 and M1088 axles? there should be one since the M1088 goes a bunch faster than the M1078

 

[NDT]

The axle ratios are the same as are the transmission ratios. MTV has more horses though.

 

[mkcoen]

The axle ratios are the same as are the transmission ratios. MTV has more horses though.

So will a reprogram of the M1078 increase speed?

 

[Lmtv772]

So will a reprogram of the M1078 increase speed?

The M1088 we have got a C7 engine rather than a 3116, they have about 100HP more, i think.

 

[Suprman]

First variants have a cat3116. Whichever model you choose the engine is governed at around 2600rpms you can go around 57-59mph. The early A1 trucks have the Cat 3126 and then switched to the C7. You can reprogram for more HP but I dont believe they go any faster. You can put certain MRAP gearing into the axles for more highway speed at a trade of loosing some low end torque.

 

[mkcoen]

Thanks Suprman. Was hoping a reprogram would work as it would be cheaper and less work.

 

[Suprman]

There is no reprogram on a first gen truck. Its a mechanical motor. You can have allison adjust the shift pattern a bit but the ratios are what they are.

 

[Lmtv772]

Some like the 3116 better because they're all mechanical and you can synchronize all the injectors and do fuel timing ect and fuel settings. Plus I think you can run several different fuel blends...

 

[Suprman]

I like the 3116 I can self troubleshoot it. I just don't know enough about the computerized engines. The local cat mechanics recommend the 3126 over the C7 they are not fond of the whole C line of engines.

 

[Hwhomes]

My truck has this axle rs15611nfsf. Is this a 2 1/2 ton or five ton? I'm hoping 2 1/2 as I can get air lockers for it.

 

[SP5]

I believe the axle is a RF-12-611,, the -12 axle uses air operated drum brakes as standard. The -19 axle uses hydraulic actuated drum brakes as standard. Both are available with either hydraulic or air operated disc brakes, the disc brakes use a diff hub than the drum brakes. With discs, the -12 axle uses the "quadraulic" 63mm pistons, and the -19 axle uses 74mm
pistons.
All of the above is IIRC.

 

[Suprman]

The 4x4 is a 2.5 ton and 6x6 a 5 ton.

 

[J5M116]

Good Morning All (M1078A1) aka Alaska John
how much backlash should I have in the rear axle?