Wehring LMTV Mods

[coachgeo]

For those with 6x6.... these should fit your rear most axle cause the innards are the same. For the Intermediate axle... not sure. There is a standard Ring and Pinion behind the offset box that goes into the pumpkin like any other axle per manual image*... the part numbers for things between the models are similar... but not the same. Interesting. Maybe someday we can get side by side pics to help discern the differences. Green shows units with same part # but all the others are similar between 4x4 and 6x6...... but not the same exactly (by numbers)

6x6.........................................vs.....................4x4
note: bold underline shows where the numbers slightly differ between the two

Pinion Gear ..... A-41631K2 ......... vs ...Pinion Gear ..... 41633K2
Int. Axle Ring... A-41100K2......... vs ... almost same as 4x4 rear / with 6x6 being ...00K2 and 4x4 ...02K2 as shown below
rear Axle Ring.. 41102K2-1.95..... vs ... rear axle Ring.. 41102K2-1.95

* images and part #'s from manual pages of:
LMTV Rear Axle image and and part numbers from...... TM 9-2320-365-24P pages 374-376 (section II, Group 1102, Image 135)
MTV Rear Int " " " ..................."..........."............... TM 9-2320-366-24P-1 pages 499-505 (Section II, Group 1102 Image 162)
MTV Rear Most " " ................"................"............. TM 9-2320-366-24P-1 pages 494-497 (Section II, Group 1102 Image 161)

 

[DiverDarrell]

For a 6x6 a locker up front and a locker in the back. Then run extended skid steer track over tire option and instant half track

 

[dronsen]

coachgeo-

Sorry if my question seems naive - I'm not a "diff guy"...

Is your post offering that a swap of these three parts is all that's needed for 3.07 change (as opposed to needing entire gear set part)?

Thanks in advance for explaining - I'm looking to upgrade to 3.07 on M1088

 

[scottmandu]

What about the rear air lockers on certain MTV's? I've seen reference to them in the manuals but have not seen one on a truck.

 

[Suprman]

In "mode" the trans locks the transfer case center differential forcing both driveshafts to turn at the same speed. And I believe at the same time on the 6x6 it locks the middle axle power divider output to the rear axle the same way.
Will

 

[DiverDarrell]

coachgeo-

Sorry if my question seems naive - I'm not a "diff guy"...

Is your post offering that a swap of these three parts is all that's needed for 3.07 change (as opposed to needing entire gear set part)?

Thanks in advance for explaining - I'm looking to upgrade to 3.07 on M1088

on a m1088 the center axle messes you up. The pinion gear I believe is made differently, so it's more than just a ring and pinion swap. You would have to consult the tm's and compare part numbers. For the other axles its an easy center section swap.

 

[coachgeo]

coachgeo-...Is your post offering that a swap of these three parts is all that's needed for 3.07 change (as opposed to needing entire gear set part)? ...Thanks in advance for explaining - I'm looking to upgrade to 3.07 on M1088

Yes but it is not practical and results in higher labor cost. Your right in thinking that all one needs to upgrade is the Ring and Pinion but to get to them from a used axle requires additional assembly of a unit that comes out all in one piece. (Center Section). Less labor to just pull the center section from axles with wanted R&P inside and just swap whole Center Section into your axles.

One MIGHT can find R&P's on Govt. Auction site and do the complete remove, disassemble, reassemble with new R&P of each of your own axles Center Sections. I do not know if R&P's show up on auctions or not. Others may have more info on if they come up occasionally or not.

 

[coachgeo]

on a m1088 the center axle messes you up. The pinion gear I believe is made differently, so it's more than just a ring and pinion swap. You would have to consult the tm's and compare part numbers. For the other axles its an easy center section swap....

The part #'s are listed earlier in this thread for comparision

 

[coachgeo]

What about the rear air lockers on certain MTV's? I've seen reference to them in the manuals but have not seen one on a truck.

Understand the confusion. Use to confuse me too. Took a lot of reading and listening to Will to figure it out. Think got it right now.

Like Suprman/Will says.... the ONLY air locker on 6x6's is NOT inside an axle but inside the Power Divider. Think All MTV's have this. It is used to lock the first axle ;in the pair of rear axles, to the rear most axle. 90-99%? of the time the air locker is NOT activated, thus the rear most axle just plays follow the leader and is not powered. Only in some conditions... when first gear is needed , and in offroad mode for example, is only time the computer activates the pump to send some air to the locker to activate/lock it, resulting in both rear axles being powered.

On past commercial 6x6's one manually locked the two rear axles together ONLY when needed. And unfortunately was done by forgetful or un-knowledgeable drivers when NOT needed too, resulting tearing things up. When not needed it can cause similar issues as when one drives in 4x4 on pavement where tires can't slip, causing gears to bind up. MTV uses same concepts thus in the FMTV design; as is most trucks with dual rear axles these days, locking the two rear axles together is done automatically under certain conditions to prevent damage. You can't manually activate it.

 

[akwildfire]

So question is there a easy way to reset the CTIS set tire PSI settings? Mine will only put in 45psi on the highway setting. I can not find any info on if its a adjustment or a new regulator that is needed. Anyone able to help. I thought maybe you have delt with this changing tires around or did you remove the system sense your going over to 22.5s?

 

[Suprman]

Maybe a bad pressure transducer. Supposed to be 70 highway psi I measure around 65 on my trucks though.

 

[mkcoen]

Maybe a bad pressure transducer. Supposed to be 70 highway psi I measure around 65 on my trucks though.

Does that depend on model? I thought the -10 said 55psi for highway. I just got mine working yesterday and didn't check the pressure aftrwards.

 

[akwildfire]

Thanks that helps. Is there a easy way to check it?

 

[Suprman]

Yup the manual does say 55psi for highway. I think some of the mrap controllers are programmed for a bit higher pressure and they are cross compatible.

 

[akwildfire]

I just downloaded the book. That seems like a soft tire. Mines like driving a loader down the road. Im going to try disconnecting the box and manualy fill the tires and see how that does

 

[mkcoen]

Do you have Michelins or Good Years? Before I fixed my CTIS I kept my Good Years inflated to 70 psi and it rode great.

 

[tburk49760]

Do you have Michelins or Good Years? Before I fixed my CTIS I kept my Good Years inflated to 70 psi and it rode great.

and if you have michelins, which ones?

 

[akwildfire]

I have the Michelins 395 85 20. The nondirectional deep lug

 

[tburk49760]

Xzl or xml. Major difference in tread pattern and likely wear.

 

[coachgeo]

Do the chalk test on your tires to determine best highway pressure. Search the net or YouTube for more details and examples of this.