Monday, October 24, 2016

My Thoughts On Towing

I don't claim to know it all.

Why Tow

It's a life style choice. We would not travel without our Jeep. We take our Lazy Daze places many would not. We take the Jeep to the places the LD can not go. If your traveling style means short duration trips, full hooks and stopping at scenic overlooks. You should be fine without a toad.

What To Tow

Unless you intend to do some serious off-road wheeling, I would discourage getting a TJ or JK Jeep. They are special purpose vehicles for rock climbing, etc. If you want the convenience of a transfer case for towing, but don't intend to drive the Moab trails, you would save weight and money getting an older Grand Cherokee or a newer Renegade. 

If you don't need a Jeep, there are some other vehicles, such as the Forester, which can be towed four down with few restrictions.

Got to have a Jeep? Consider the lighter weight TJ model that was built through 2006. If you want a new JK Jeep, consider the lighter 2DR rather then the popular 4DR. Understand that the rear seat on a 2DR is only suitable for dogs and small kids, but it's lighter and turns sharper than the Unlimited. Our rear seat came out the day we brought the Jeep home.

The Hitch

An ongoing topic in the Lazy Days forum is towing over 4,000 pounds which is the rated maximum for the factory hitch. "Beefing up" the hitch is the common suggestion. What constitutes "beefing" is nebulous. How does one find a "good hitch shop". I am not willing to trust that just anyone knows how to do it. All I can say is that doubling the attachment to the frame might be the way to go. That seems like a simple task to me. Weld on two additional braces. Maybe that's all that's required.

We have towed a 4,250 pound Jeep for 95,000 miles on the factory hitch. Since 10% is a common engineering safety margin I am comfortable. I did upgrade the bumper bolts to Grade 8 with larger washers. I found several loose nuts in the process. I used blue Locktight when I put on the new bolts. The bolt upgrade may have increased the tow capacity? Whatever you are towing this is a MUST MOD. Thanks to Larry Wade for this excellent improvement.

September, 2016
I followed Ed Daniels into a hitch shop in Moab, UT. Ed has a TK. The shop owner, Ben Wilson, did not think it needed anything extra to safely tow a 2016 Wrangler. Ed said he liked to tow down rough dirt roads. So Ben added a corner gusset to "beef it" up. Ben looked at my MB and saw no way to add any structural integrity. He drew out the TK design and compared it to the MB design. Way different. He saw no signs of metal fatigue after towing 95,000 miles. No wrinkles in the paint that would indicate the metal has been flexed. I felt better. I asked him to tack weld the adjustable part of the hitch, so it could not move if the bolts ever came loose again. And left feeling better about the LD hitch. If you are in the Moab area and want a pro to check yours out, the man to see is Ben Wilson at 435-260-2044.

Larry Wade's backing plate

 Ed Daniel's TK mod
 Ed Daniel's TK mod

Our MB tack welded just to prevent any movement in case of a loose bolt

The Crux Of The Matter

If I were looking at a used LD I would be leery of one that had a beefed up hitch. I would wonder exactly how much they had been towing? There is not only the 4,000 hitch limit, there is the almost ignored 20,000 pound GCWR. That rating decreases as the elevation increases. I would wonder how the extra weight has affected the transmission? Did the owner monitor the transmission temperature with a gauge? How often was the fluid changed. I would look at the color of the fluid. 

Downhill, the extra weight is stressing two components, the transmission and the brakes. Assuming you are using Tow Haul and allowing the engine to partially brake the decent, the  extra weigh can spin the transmission toward the red line. Using the brakes more heats the rotors. Have you priced those lately? 2008 rigs come with larger rotors that should help. [Had I known Ford was going to make that change, I would have waited a few months to place the order]

It's balancing act to get the toad brakes to engage correctly. You sure don't want them coming on too hard and braking the Lazy Daze. The ability to set when and how hard the toad brakes come on are an advantage of systems like SMI makes. 

Important, But Neglected GCWR

You can move your rock collection from the LD to the toad axle, but all of the weight counts toward the GCWR. There is no free lunch. 

The GCWR is reduced 2% per 1,000 feet of elevation. This applies to ALL E450 chassis with the V10 engine.

An example:

We unhook, if we are going over 6,000 feet for any distance. Think of that long steep grade west of Denver. Our MB is 13,700 + 4,250 for the Jeep, for a total of 18,000 -  inside the max GCWR of 20,000 at sea level, but not above 5,000 feet. Folks, you should be just as concerned about the GCWR as the hitch limit.

Don't care for my example? Think you can load up the toad and have that free lunch? Here's what Wikipedia has to say on GCWR.

Bottom line, if your are towing much over the rated capacity of the hitch, it's a good thing to have it doubly connected to the frame. It's is important to weigh both vehicles, to monitor your transmission temperature and to not tow at higher elevations. And know that a informed buyer may see the beefed up hitch as a concern.

Don Malpas

See also