Western Canadian Rockwell, MRAP to Deuce adapter plates. Do I have a problem?

[Jbulach]

I just received a couple of MRAP to 2-1/2 ton adapter plates from Western Canadian Rockwell and was a little surprised at the chamfer (or lack there of) in the lug holes. Do I have a problem? What say’s the horde?

 

[Fatalid]

I got mine from Boyce out of Utah... They had more of a chamfer on them.

I don’t think it’s that big of a deal though.

The biggest issue with most of these manufactures is that they aren’t putting a hub lip around for MRAP wheels to center on.

You're going to get more slop from the MRAP bolts in the adapter plate, then the adapter plate on the Rockwell hub.

 

[silverstate55]

You can always take the adapters to a fab shop or semi-truck wheel shop to put the proper Budd chamfer on them.

From your pics, your adapters don't quite have enough of the proper Budd chamfer for the nuts/thimbles to center the wheel on the studs with.

 

[gringeltaube]

Compare yours with the dimensions shown below...



It seems to me that Ø "B" is within specs but Ø "A" is definitely too big...?
FWIW, "A" is 1.22" for the wheels on Deuces and M37s, and around 1.28" on HEMTT and FMTV wheels.

Since we are talking about stud-piloted steel wheels, even that little chamfer will be sufficient to center the adapter to the hub. But then when torquing down to 350 ft-lbs the nuts may start deforming that narrow seat, depending on how soft that steel is.

Just check your lug nuts frequently!

 

[Jbulach]

Compare yours with the dimensions shown below...

View attachment 761465

It seems to me that Ø "B" is within specs but Ø "A" is definitely too big...?
FWIW, "A" is 1.22" for the wheels on Deuces and M37s, and around 1.28" on HEMTT and FMTV wheels.

Since we are talking about stud-piloted steel wheels, even that little chamfer will be sufficient to center the adapter to the hub. But then when torquing down to 350 ft-lbs the nuts may start deforming that narrow seat, depending on how soft that steel is.

Just check your lug nuts frequently!

“A” is big at 1.288, compared to 1.225 of my stock accuride wheels.
“B” is small at 1.33, compared to 1.5 of my stock accuride wheels.
The nuts that I’m using off a M939a2 measure 1.26 at the start of the taper, so yes they will seat, but I don’t think that small of a bearing surface is a great idea. Guess I’ll torque them down and see how much the lugs mash their way into the adapters, then if I don’t get that warm and fuzzy feeling I’ll give WCR a call and see if they have excuses or resolution.

 

[Mrmag1]

WCR is where I got mine from, I haven’t had a problem but I can’t remember if there was any chamfer.

 

[gringeltaube]

“A” is big at 1.288, compared to 1.225 of my stock accuride wheels. .......

Not a problem.

“B” is small at 1.33, compared to 1.5 of my stock accuride wheels.

Good; that means you (or a machinist) can still modify them for the correct chamfer. Not a big deal - if you have the right tool.
And to keep this simple, even a conical (non-spherical) seat at 55° taper would do.

 

[Jbulach]

Torqued the plate to 500 foot pounds with no change except for maybe a slight truing of the chamfer angle and slight deformation in the nut. Happy feeling gone....

I emailed Western Canadian Rockwell, received excuses, and offer for return for refund. At this point due to impatience, I’m going to run them and see what happens, and will report back. If you have adapters from them, make sure your retorquing your wheels like we’re supposed to anyhow. I guarantee any damage caused is going to be attributed to lack of retorquing/loosening, catch 22 BS. We’ll se what I get for saving a few bucks...

Would love to see what others adapters from them look like?

 

[Jbulach]

WCR is where I got mine from, I haven’t had a problem but I can’t remember if there was any chamfer.

Recheck your torque, ASAP, and if you get a chance, zip one of your nuts off and snap a picture for us.

 

[gringeltaube]

...... and slight deformation in the nut. .................

... That should not happen really, because OEM (correct) nuts are hardened.

Try with a regular file; if it grabs and actually removes material, discard those nuts and get the good ones.

 

[winfred]

don't think id be comfy with that sharp edge or torquing the lugs to 500, i think the lugs are only supposed to be around 350 and the sharp edge may concentrate the force and deform lowering the torque, could lead to a cascade failure and launch a wheel after popping the studs. here's my adaptors from ebay for reference, had a 7th plate chamfered on both sides for the spare as my rear hubs aren't flipped so it can go front or rear without flipping the adapter plate

ps thats the weight of the adapter plate, beadlock and the hardware to bolt it to the rim

 

[Jbulach]

don't think id be comfy with that sharp edge or torquing the lugs to 500, i think the lugs are only supposed to be around 350 and the sharp edge may concentrate the force and deform lowering the torque, could lead to a cascade failure and launch a wheel after popping the studs...

I think 450-500 is pretty standard.Its also what the TM for my trailer calls for, single or dueled.

 

[Jbulach]

Check your nuts!