Dualmatics on the Rear

1941 - 1945, MB, GPW modifications, sugestions, and ideas, official MWO's and unofficial WWII field mods NO EBAY or COMMERCIAL SALES.
ndnile
G-Second Lieutenant
G-Second Lieutenant
Posts: 551
Joined: Wed Sep 17, 2014 8:09 pm
Location:

Re: Dualmatics on the Rear

Post by ndnile » Sun May 20, 2018 1:22 pm

lt.luke wrote:
Sat May 19, 2018 4:01 pm
Why not buy a trailer and do it right? Way less wear on all involved Jeep components.
Fair point. Space is at a premium at my house. I know I could keep the jeep parked on the trailer, but the trailer will still be larger than the jeep. Also I would need to back in the trailer + jeep to where I park it which would make getting the jeep out whenever I wanted to drive it a bit of a puzzle problem.

If there is no good rear axle lock-out solution I'll just keep with what I have and rent a trailer for the really long hauls.

Thanks, Doug
Doug
Sacramento Area
1943 Willys MB
1943 GPW-125334 (Sold)
1962 M170
1959 Willys Wagon


Bart1015
G-Major
G-Major
Posts: 913
Joined: Wed Apr 16, 2014 6:20 pm
Location:
Contact:

Re: Dualmatics on the Rear

Post by Bart1015 » Mon May 21, 2018 6:57 am

Ndnile,

I have seen this done before and its really nice for flat towing. A few months ago talked to a MV owner who has front and rear locking hubs.

He told me he had cut the ends off of the rear axel shafts and welded on the splined ends from a set of front axels.

He made a jig to ensure everything was lined up and when he was done he said he had the shafts balanced at a driveline shop. It is important to get the length correct. I am sure there was more to it.

But, as long as they are lined up and somewhat balanced to should work fine. The hubs will contain the outer bearings when free wheeling, when locked, the hubs act as a solid unit like the original unit.

The locking hub type is important. Some brands require C-Cips, some bolt to the shaft, and others need nothing to secure them to the spline.

The Dualmatics will work fine. I actually like them much better then others.

Ndnile, I have finally located all the parts to build a set. I am still about a year out until I get to the axels but I will let you know how it goes.

Brett
1942 VEP GPW, J-2 winch, BC-659, 1919a4
1945 GPW, 1943 MBT
Sold - 1967 M151a1, 1943 MB, M416
www.ToThePointPolygraph.com

ndnile
G-Second Lieutenant
G-Second Lieutenant
Posts: 551
Joined: Wed Sep 17, 2014 8:09 pm
Location:

Re: Dualmatics on the Rear

Post by ndnile » Mon May 21, 2018 7:24 am

Ndnile, I have finally located all the parts to build a set. I am still about a year out until I get to the axels but I will let you know how it goes.
Sounds great Brett, thanks!

Cheers, Doug
Doug
Sacramento Area
1943 Willys MB
1943 GPW-125334 (Sold)
1962 M170
1959 Willys Wagon

Joe Gopan
Jeep Heaven
Posts: 49841
Joined: Sun Mar 02, 2008 12:37 pm
Location: Proving Ground

Re: Dualmatics on the Rear

Post by Joe Gopan » Mon May 21, 2018 7:53 am

And remember that there will be times your Parking Brake is not doing what you expect it to do.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

Marty, SoCal
G-Lieutenant General
G-Lieutenant General
Posts: 6319
Joined: Thu Mar 09, 2006 10:34 am
Location:

Re: Dualmatics on the Rear

Post by Marty, SoCal » Mon May 21, 2018 9:46 am

As an alternative, if only needing it a few times a year, one could simply remove the rear driveshaft from the rear axle flange, wrap the u-joint with saran wrap and rubber bands and strap it to the underbody.
43 Ford GPW 92098
53 Dunbar Kapple M100
Sold: 61 CJ-5, 41 T207 WC-1 Dodge closed cab pickup
MVPA #8266
USMC Tanker (1811, 1812), 85-93
ASE Automotive Master tech, former Chrysler-Jeep Level 4 Mastertech, CA state EA smog license

User avatar
JAB
G-General
G-General
Posts: 9587
Joined: Fri Dec 13, 2002 5:25 pm
Location: under the jeep in North Prairie, WI

Re: Dualmatics on the Rear

Post by JAB » Mon May 21, 2018 12:15 pm

Don't weld on axle shafts, it will fail, eventually.
-Jeff

GR8GPN2U!!!

Image

Image

Marty, SoCal
G-Lieutenant General
G-Lieutenant General
Posts: 6319
Joined: Thu Mar 09, 2006 10:34 am
Location:

Re: Dualmatics on the Rear

Post by Marty, SoCal » Mon May 21, 2018 3:20 pm

You might be able to find a couple Dana 35 Jeep XJ or ZJ axle shafts at the junk yard then have the Dana 35 axle wheel flange and bearing seat cut off The remaining shafts can be then shortened, turned and splined to match the 10 splines used in the Dana 23. The 27 spline that came with the shafts will fit lockout drive flanges for the 27 spline hubs off a mid- 70's to 1981 CJ-7. The new machined to length and splined ends would fit the Dana 23.

Note: If you find an XJ Cherokee at the bone yard before 1989, they wont have c-clip grooves, meaning one less machine step to remove them.

Typical Dana 35 shaft:
Image
43 Ford GPW 92098
53 Dunbar Kapple M100
Sold: 61 CJ-5, 41 T207 WC-1 Dodge closed cab pickup
MVPA #8266
USMC Tanker (1811, 1812), 85-93
ASE Automotive Master tech, former Chrysler-Jeep Level 4 Mastertech, CA state EA smog license

User avatar
JAB
G-General
G-General
Posts: 9587
Joined: Fri Dec 13, 2002 5:25 pm
Location: under the jeep in North Prairie, WI

Re: Dualmatics on the Rear

Post by JAB » Mon May 21, 2018 4:22 pm

Ben Dover wrote:
Mon May 21, 2018 7:53 am
And remember that there will be times your Parking Brake is not doing what you expect it to do.
Lol! No need to elaborate on that one! Bin dar, dun dat!

Once, as a joke my friends unlocked my rear free-wheeling hubs to watch me get stuck in the mud, not realizing that the front's hadn't been locked in yet and that the parking brake, questionable at best, wasn't set. Luckily it' didn't roll away until I jumped in, as it would have been a dangerous situation. As it was, I had to steer and brake until the jeep stopped at a spot where it wouldn't roll so I could get out and lock the hubs. If you do this modification you do need a good, functioning parking brake.
-Jeff

GR8GPN2U!!!

Image

Image

ndnile
G-Second Lieutenant
G-Second Lieutenant
Posts: 551
Joined: Wed Sep 17, 2014 8:09 pm
Location:

Re: Dualmatics on the Rear

Post by ndnile » Mon May 21, 2018 7:19 pm

Ben Dover wrote:
Mon May 21, 2018 7:53 am
And remember that there will be times your Parking Brake is not doing what you expect it to do.
Joel, I didn't get your meaning until I saw JAB's response. Yes, very good point. Unintended consequences abound.

Cheers, Doug
Doug
Sacramento Area
1943 Willys MB
1943 GPW-125334 (Sold)
1962 M170
1959 Willys Wagon

The Fireman
U.S.M.C. Veteran
U.S.M.C. Veteran
Posts: 1399
Joined: Sat Sep 20, 2003 8:52 am
Location: Banjoland, So. Orygun Territorium

Re: Dualmatics on the Rear

Post by The Fireman » Wed May 23, 2018 11:56 am

Doug,

Give Sandy a call and see if he still does the conversions. I have not had any issues with the conversion since I have owned the jeep on or off road. The conversion has worked well for me, flat towing as well.

SF

Frank
The Fireman
NRG

ndnile
G-Second Lieutenant
G-Second Lieutenant
Posts: 551
Joined: Wed Sep 17, 2014 8:09 pm
Location:

Re: Dualmatics on the Rear

Post by ndnile » Wed May 23, 2018 7:24 pm

Hi Frank,

I'll give Sandy a call and see what I'm in for. You having been-there-done-that speaks volumes.

We need to meet up sometime. We're both in the NRG and I found my jeep through you, but I don't know that we've ever met.

Cheers, Doug
Doug
Sacramento Area
1943 Willys MB
1943 GPW-125334 (Sold)
1962 M170
1959 Willys Wagon


Post Reply

Return to “MB GPW Modifications”

Who is online

Users browsing this forum: No registered users and 41 guests