FMTV High Speed Gears

[wehring]

Open Diffs... verified.

I run the 70mph rated XZLs with recent date codes for precisely this reason.

Justin

 

[auctionaddict]

Anyone that's done that swap, can you verify that these trucks do or do not have locking differentials in them?

Also, do the caiman axles have lockers?

No and NO there both open diffs..

 

[Derrickl112]

.

 

[ke5eua]

Has anyone come up with a solution to fix the speedometer?

 

[steve6x6x6]

Open Diffs... verified.

I run the 70mph rated XZLs with recent date codes for precisely this reason.

Justin

I have looked at the chart and the max. speed for all XZL tires is 55 MPH.

 

[Rambling Wreck]

No and NO there both open diffs..

Is there perhaps a variant of the LMTV that does have locking diffs? I've been researching this but I keep coming up with conflicting information. In particular I have found several places claiming that the LMTV's have "Full-time All-wheel Drive and Integral transfer case with locking interaxle differential".

 

[wehring]

Direct from Meritor and Dana... No but they will make a prototype Detroit locker for $4000

justin wehring

 

[Rambling Wreck]

Yeah, I saw where that was said, before I posted. However, since I've seen conflicting information, I was hoping that someone else might shed some light to show that the prototype locker wasn't the only option.

 

[steve6x6x6]

Direct from Meritor and Dana... No but they will make a prototype Detroit locker for $4000

justin wehring

The Detroit locker PN # 225-S-92, for all LMTV.

 

[steve6x6x6]

The Detroit locker PN # 225-S-92, for all LMTV.

OK the rest of the story. These DT. lockers were obsoleted in 2002. I have talked to Brent, (we go way back into the 1990's) he is the Engineer inside Eaton. I have looked into another option for a locker but it to was obsoleted to in 2002. 11 million dollars of Trac-tech's inventory in 2006 was scrapped when they were bought out, the very items we are looking for. I am working on a heavy duty locker for the LMTV that will require machine work to the carrier for it to fit. The (4) pin size would be changed from 3/4" to 7/8". I would need your carrier in exchange, i have some to get started.

 

[wehring]

Count me in Steve! Thank you for putting in the effort

justin

 

[Firetoy]

Do you guys know if they will ship diffs?

 

[wehring]

I have an extra set and I will ship

justin wehring
979 997 3112

 

[Firetoy]

pm sent

 

[m1079]

Any increase in MPG at cruise?

 

[wehring]

It was basically a wash for me. 6.5 before and after

 

[NDT]

It was basically a wash for me. 6.5 before and after

I'll never understand why a modern turbocharged/intercooled empty 17,000 lb diesel truck gets the same or worse fuel economy as a loaded 80,000 lb class 8 big rig.

 

[patracy]

I'll never understand why a modern turbocharged/intercooled empty 17,000 lb diesel truck gets the same or worse fuel economy as a loaded 80,000 lb class 8 big rig.

Underpowered.

 

[m1079]

Has anyone done a C7 swap or looked into dual fuel CNG injection yet?

 

[Terrh]

Underpowered.

okay, but my 7.3 truck with 15klb behind it is just as underpowered, weighs more, has worse aero and gets more than double the MPG.

I'll never understand why a modern turbocharged/intercooled empty 17,000 lb diesel truck gets the same or worse fuel economy as a loaded 80,000 lb class 8 big rig.

I think there a bunch of factors, this has bugged me a lot too. I have gotten 11 MPG in my freightliner grossing about 60,000lb. (proof) http://i.imgur.com/5hbLRlh.jpg

One of the biggest factors has to be gearing - my freightliner spins 1300rpm at 55mph.

Full time AWD can't be helping either, and I suspect that those CAT engines are just fuel pigs by design.

It would be interesting to find one with a bad engine and do a 5.9 swap and see what the MPG does.