Basically the more out-of-level the toe bar is, the more stress that is placed on the tow bar arms. This is made worse by the weight of the toad during braking.
An extreme example: During heavy braking of any vehicle the front end goes down and the rear end goes up. This is normal for any vehicle - the nose dives and the rear flies. Now add a tow bar to the back of a MH that is too far out of level with the toad. It doesn't matter if you have an H1 that is 14 inches higher the receiver, or my smart car that is 4 inches lower than my receiver. The tow bar's U-joint doesn't have a tongue weight rating. It's not designed to carry the weight of the toad. It's designed to have the toad push into it. Granted, the front end of a toad may get air from time to time - usually on bad campground roads (happened to me in Coeur d'Alene) - and the tow bar companies know this. It's the
sustained stress on the U-joint and tow bar arms from an out-of level towbar that needs to be avoided.
I drive a former Cruise America rental unit that is already low to the ground - by design. I have a 4 inch drop extension on the receiver for my rolling snot bubble. I don't have training wheels on the receiver. Every driveway and curb cut that that I enter, I do it slowly and at a 45 degree angle. If I cannot enter without bottom-ing out then I don't enter at all.
This is from Roadmaster:
This is from Ready Brake:
http://www.readybrake.com/faq.htmlReady Brake's FAQ wrote:
What other issues could I run into?
Tow bars need to be level to the ground when installed correctly. The National Standard for correct tow bar levelness is (+) or (-) 2" inches. This allows for a forward push by your towed vehicle. Having the tow bar too far from level puts a great deal of stress on your towing system and can also cause you to lose control of your RV in adverse conditions when heavy braking is applied. To measure levelness just subtract the difference in height of the center of your RV receiver from the ground with the height of the center of your baseplate tabs on the towed vehicle from the ground. Most baseplate brands list an approximate tab height for each vehicle on their websites if you do not have a baseplate installed to measure yet. If a drop or rise is needed we also manufacture hitches for this.
