5th Wheel Clearance Questions

[boonsur]

I have a 2003 QC, 3500 4x4 DRW. As I'm shopping for trailers/negotiating axle flips, etc. , what height should I shoot for, from the ground to the bottom of the 5th wheel BODY. I'd like to have 8" of clearance between my bed rails. Maybe the question is, how much will the rear of the truck sag, with ~2,000 hitch weight in it.



Another question to ponder:



Which would yield better clearance in tight (hill) maneuvers? The truck hitch higher, or lower (adjusting the trailer pin accordingly)? In other words, would it be better to raise the truck hitch and tuck the trailer pin closer to it (higher), or lower the truck hitch & extend the trailer pin down to accomodate)? Hard question to verbalize , but maybe someone can give theory why one would be better.



Thanks.

 

[Dkevdog]

General rule of thumb- is 6" of clearance is ok. I however, prefer more. I have about 8" when the truck/trailer sits on level ground. And there are unlevel terrain situations where even that is a close call. When mine was set at 6" I had two incidents. One of which resulted in the need for a new tailgate, the other was ver minor and did no real damage.



Bottom line is, Yeah, you can say "Oh, I'll never take my trailer on a driveway like that, or uneven terrain, blah blah. "



Truth is different- you don't know what you'll be doing in the trailer or where you'll take it, and going over an unusual driveway out in the middle of knowhere trying to get fuel is NOT the time nor place to find out you were wrong.



As for truck squat? It depends on many things, age of springs, truck, etc. My 01 3500 sits about 2" with a tounge weight of 2000lbs.



Your measurements should always be with a loaded trailer.



Kev

 

[boonsur]

Minimal Difference

It was bugging me, so I did a quick layout (attached). It appears there would be a "minimal" clearance gain by raising the truck hitch (shown on the left side of the layout). And this was considering a pretty big variation in the hitch height. It appears there would also be less swing away, but again the gains are minimal. So, it looks like I should set the truck hitch wherever it best matches the 5th wheel hitch, and be done with it. Oh well...

 

[Casey Balvert]

Boonsur, that's pretty cool. I always felt that it was best to lower the pin than to raise the hitch. By raising the hitch, you raise the hitching point and based on simple leverage, lateral forces exerted by the trailer would have a greater effect on the truck. Theoretically anyway. In reality it probably doesn't have any noticeable effect. So go with whatever floats your boat.



Casey

 

[boonsur]

Adjustable, On-the-Fly

Myself and a friend from work spent quite a bit of time, concepting a hitch that could be raised and lowered hydraulicly. If you ever got into a tight situation, you could raise it & prevent damage to the bed. Came up with some cool ideas, but never did anything about them. Maybe in a few years someone will get rich of the idea, and we'll keep going back to the same job, day after day .

 

[tgrfan2]

My friends 03 sags just to the overloads with about 2600# of pin wgt. In fact, on certain bumps the overloads "pop" as they come on and off the blocks. I would recommend trying as is . You can add air bags if you want to level the truck later. On my 2500 it takes 50# of air to bring my truck back to no load position with 2600# pin weight.