M35 locking hubs question

[Sgt Jiggins]

Howdy,

While specing some lockout hubs for the front of my M35, I ran across mention of a locking hub installed on the middle axle on an M35A2. As in, the one side of the truck, on the front of the two rear axles.

Is this a thing?

Thanks,
SJ

 

[doghead]

It can be.

 

[Sgt Jiggins]

Hypothetically speaking, if a guy (or gal) were considering such a mod...

1)what pros/cons are there to putting a locking hub on a rear axle?
2)what would be involved? (in this case it's an M35A3 if that makes any difference)
3)and of course... is it worth doing so?

I know #3 is a bit subjective. So, to that point, I put locking hubs on the front of my '51 M37 20 years ago. Never regretted it. And other than the exhaust, it was really the only visible mod to the truck. So I'm no purist, but I tend to keep it "looking" stock (from the outside anyhow). If that helps...

Thank you,
SJ

 

[cattlerepairman]

https://www.steelsoldiers.com/showthread.php?32407-front-lockout-hubs-or-rear-lockout-and-axle
https://www.steelsoldiers.com/showthread.php?36943-Lockout-hubs
https://www.steelsoldiers.com/showthread.php?17563-20-Minute-Install-Locking-Hubs
https://www.steelsoldiers.com/showt...hubs-What-history-of-use-MPG-change-with-them

 

[Sgt Jiggins]

After "doing a doghead" (and RTFM), I do have a question: what's a good source of those double-splined axles to convert the front of the 2 rear axles with?

 

[doghead]

A google search for "rockwell 2.5 ton axle shaft" will get you a bunch of places that make performance and normal parts for them.

Here's the first one I clicked on. https://www.ouversonusa.com/rockwell_16spline.html

 

[montaillou]

Not too long ago I was turning around on a somewhat narrow, gravel driveway with a steep drop-off on both sides. No one else was around and I don't (yet) have a backup camera. After I got the truck turned around, I got out and noticed that my furthest rear axle had completely left the driveway and it was the middle axle that dug in the slope. Had I had lockouts on that axle, I would've ended up sliding down the hillside. So, I guess it depends on what kind of driving you do, and how cognizant you are about where your power is.

 

[kovi]

what all is involved in installing a lockout on the intermediate axle? obviously a double spline axle and a hub. is it as simple as swapping those out with the oem axle?

 

[cattlerepairman]

Yes.

"But....why?" is my question. Fuel economy? LOL. Not even going there. Hub and axle cost more than your fuel savings if you drive the truck as much as most people do. If it is your daily driver, well, different scenario.
With the front rear axle locked out, the empty truck can get hung up on ridiculous obstacles, such as a traffic calming device ("hump"). Again...why? Maybe if you only do parades and the truck never leaves the pavement.

I do not routinely "off road" my truck but it does see unpaved roads and the odd goat trail. It does not take much to need both rear axles pushing to avoid getting stuck. An uphill start on a loose gravel road will do it. I would not want to have to jump out and engage the rear axle to get un-stuck each and every time.

Lockout hubs on the front are sensible; they reduce steering effort, drag and wear on the front axle drive system.

 

[kovi]

Yes.

"But....why?" is my question. Fuel economy? LOL. Not even going there. Hub and axle cost more than your fuel savings if you drive the truck as much as most people do. If it is your daily driver, well, different scenario.
With the front rear axle locked out, the empty truck can get hung up on ridiculous obstacles, such as a traffic calming device ("hump"). Again...why? Maybe if you only do parades and the truck never leaves the pavement.

I do not routinely "off road" my truck but it does see unpaved roads and the odd goat trail. It does not take much to need both rear axles pushing to avoid getting stuck. An uphill start on a loose gravel road will do it. I would not want to have to jump out and engage the rear axle to get un-stuck each and every time.

Lockout hubs on the front are sensible; they reduce steering effort, drag and wear on the front axle drive system.

if thats all it is...a pull n swap... I will seriously consider this. the money savings in tires is enough to justify it in my book

 

[Recovry4x4]

The 3rd lockout can save you a bunch on tire wear too. How many folks roll out tire circumference and properly match your tires? How many know how? If you have 8 identical size tires, the point would be moot but nobody does. Lets see if someone knows the formula I posted on the MV Mailing list back pre-Steel Soldiers. My jaunts were 700 miles each way to the GA rally and made some 2500 mile trips. You can see the tire wear on a 2500 mile trip if they are not matched. The 3rd lockout solves that issue with a twist of the wrist.