Driveshaft Removal when Towing

[vettenuts]

I have a 2005 W24 chassis and was following a thread in the Class A section about towing and driveshaft removal. One of the thread contributors mentioned that the bolts that are used for retention of the U-Joint straps are torque to yield, i.e., one time use.

Does anyone know if this is the case for the Workhorse chassis? Wondering if I should pick up a set for my spare parts bin in case I am ever towed.

[BFlinn181]

If you break down and need to be towed, I'd think that while the RV is being repaired you'd have time to buy bolts, if they are required. Not sure I'd pack spare parts like that, it might overload your RV and cause you to break down!

[vettenuts]

I downloaded the service manual for the Dana differential and what is even more concerning is it states not to tow with front wheels raised because it will starve the pinion assembly in the differential. The manual states the axles should be removed and the differential capped with plates to prevent fluid loss so the pinion assembly doesn't rotate. This was all new information for me.

[PJStough]

Originally Posted by vettenuts

I downloaded the service manual for the Dana differential and what is even more concerning is it states not to tow with front wheels raised because it will starve the pinion assembly in the differential. The manual states the axles should be removed and the differential capped with plates to prevent fluid loss so the pinion assembly doesn't rotate. This was all new information for me.

Wouldnt driving up a hill create the same conditions as towing with the front wheels raised off the ground?

[CJ7365]

Originally Posted by vettenuts

I downloaded the service manual for the Dana differential and what is even more concerning is it states not to tow with front wheels raised because it will starve the pinion assembly in the differential. The manual states the axles should be removed and the differential capped with plates to prevent fluid loss so the pinion assembly doesn't rotate. This was all new information for me.

Waiting for all the WH chassis owners who have had their RV towed to chime in

[M&EM]

Mine was towed 10 miles to a service center. Driver was well prepared to disconnect drive shaft and carefully secure bearing caps and bolts. He also turned over all the parts and had the mechanic verify it before he left. The tow truck was as long as my rig. The front wheels were raised on a very slim fork arrangement with very little space to the pavement. No concerns were mentioned about pinion lubrication.I wouldn't have thought there would be much load on that pinion bearing with no driveshaft.

[Arch Hoagland]

My W22 was towed 70 miles with the front wheels up and I've never heard of replacing any bolts nor did I have any rear end problems afterwards.

[vettenuts]

Well, until I downloaded the service manual I was unaware as well. However, this is straight from the service manual:

"WARNING

Do not lift the front wheels (non-drive wheels). This alters
the oil’s position in the drive axle, draining it away from the
drive pinion and its bearings. If the pinion is rotated under
these conditions for any period of time, bearings will overheat
resulting in axle damage or failure.

This is impossible to lift the drive wheels, remove all axle
shafts to prevent gear rotation and cap the wheel hubs to prevent
loss of lubricant and a possible road hazard. See the following
section Proper Vehicle Towing with Wheel Differential
Lock for removal procedure."

As noted by M&EM, I would think that minimizing the angle would prevent this from happening. I could understand if it were way up in the air. One other thought, I believe this differential is used in some heavy duty pickup trucks as well. Towing a pickup with the much shorter wheel base might result in this issue.

[BFlinn181]

There's also a good chance that the warnings are put in by CYA lawyers to prevent lawsuits. Your differential is well lubed, I'd be very surprised if you could lift the front end of a long wheelbase RV high enough to prevent adequate lubrication, especially when being towed. To raise the front that high, the tail would be carving grooves in the pavement.

Rather than stocking driveline bolts, and worrying about tow angles, perhaps you could put the service manual to better use and make sure you service the RV regularly so it doesn't break down.

Murphy's law sort of guarantees that you won't have the proper parts stockpiled when you break down, so just enjoy your RV and depend on UPS, USPS, FedEx, and the like to make sure you can get parts delivered promptly when you do need them.

[rockbound]

Yeah, CYA lawyers. I run a low pinion Dana 60 rear axle in my Jeep TJ w/ a 4" lift. The pinion angle is set at 11* and pointed right at the transfer case. If compared to a Moho, the tow truck would have to lift the front end 10 feet.
If the axle is very low on gear oil, maybe towing it at 1 mph for a 100 miles might damage it. Or you could look at it this way, when normal driving the gear oil is being slung around pretty good in the third member, the same would be true if being towed. Or you could look at it this way, stir your coffee with an egg beater.

Steve

[AKIQPilot]

This is one of the strangest thing I have heard concerning towing a motorhome.

As is the case with most rear axles, the pinion bearings get lubrication from the ring gear picking up lube oil and slinging it forward. There is a hollow passage in the casting of the carrier that the oil from the ring gear is directed into. Oil is directed into this passage above the centerline of the pinion. The oil drains through the pinion bearings and then drains back to the center of the case through a smaller passage cast into the lower half of the carrier. These two castings can be seen from the outside when looking at the carrier. These castings are what give the carrier or axle housing it's funny shape above and below the centerline of the pinion shaft.

At very low speeds I can see how there may be inadequate lubricant being slung forward into the pinion bearings but at any speed over about 30mph it would seem like plenty of oil would make it to the pinion bearings. I suppose I could see how this may be an issue if towing long distance at 30MPH or less.

On the other hand, there may be something to it if it's mentioned in the manual. But I still have a hard time seeing how raising the pinion angle 2 or 3 degrees, by lifting the front axle off the ground, is going to starve the pinion bearings while traveling down the road at a reasonable speed.

Good discussion guys. Thanks for bring this issue up Vette.

[AKIQPilot]

Originally Posted by rockbound

Yeah, CYA lawyers. I run a low pinion Dana 60 rear axle in my Jeep TJ w/ a 4" lift. The pinion angle is set at 11* and pointed right at the transfer case. If compared to a Moho, the tow truck would have to lift the front end 10 feet.
If the axle is very low on gear oil, maybe towing it at 1 mph for a 100 miles might damage it. Or you could look at it this way, when normal driving the gear oil is being slung around pretty good in the third member, the same would be true if being towed. Or you could look at it this way, stir your coffee with an egg beater.

Steve

Good post Steve. I started my response almost an hour ago then got sidetracked. You and I are on the same page with regards to the ring gear slinging oil where it's supposed to be.

[vettenuts]

Just in case anyone wants the S130 service manual here is a link to it from the Dana-Spicer web site. Note that the link on the Workhorse web site for the S110/S130 brings up the S135/S150 service manual so the link on the Workhorse web site is not correct.

Dana-Spicer AXSM-0055 (Dana S110/S130)

[CJ7365]

Well another issue is the WH owners manual, it states to use 75w-90 synthetic, but in the Dana/Spicer Book that Vettenuts posted, this 75w-90 is only good up to 100F, so for those of us in the Desert Southwest, we are running the wrong lube, we should be running 80w140 or 75w140.