Surge feeling with 5th wheel?

[tedstundra]

I just towed my new 5th wheel with my 08 SR5 4X2 for the first time. It is relatively heavy, probably around 8500 lbs as towed. I installed air bags to accomodate the extra hitch weight. I have towed regular a TT before with no problems and was assured that the 5ver is a much easier tow. However, I experienced something new. A feeling the the truck was experiencing a surge from the trailer. I'm not sure how to explain. At first I thought it was the transmission shifting gears, but that proved to be not the case. It's as if the trailer is being buffeted by a regularly spaced headwind, which causes a the trailer to change its effective load on the truck. It is relatively evenly spaced phenom. Has any body had this experience, and if so, any explainations why and is there something I can do?

[Codiac]

Originally Posted by tedstundra

I just towed my new 5th wheel with my 08 SR5 4X2 for the first time. It is relatively heavy, probably around 8500 lbs as towed. I installed air bags to accomodate the extra hitch weight. I have towed regular a TT before with no problems and was assured that the 5ver is a much easier tow. However, I experienced something new. A feeling the the truck was experiencing a surge from the trailer. I'm not sure how to explain. At first I thought it was the transmission shifting gears, but that proved to be not the case. It's as if the trailer is being buffeted by a regularly spaced headwind, which causes a the trailer to change its effective load on the truck. It is relatively evenly spaced phenom. Has any body had this experience, and if so, any explainations why and is there something I can do?

You sure your trailer brakes are working correctly?? Not sure what kind of brake controller you have if any but I would check this first.

Is your 5th wheel secure?? Make sure there are no loose bolts or slop in it at all.

I have had my trailer surge occasionally when the holding tanks were partially full and the water surged back and forth in them. There are no baffles in holding tanks so the water sloshing back and forth can cause a surge action. However you usually only feel this when running twisty roads or when you are slowing and speeding up due to terrain or traffic.

Just some thoughts I had. I have pulled every type of 5th wheel trailer there is and never had this issue. The air bags shouldn't be causing a surge.

[Survivor61]

Originally Posted by tedstundra

I just towed my new 5th wheel with my 08 SR5 4X2 for the first time. It is relatively heavy, probably around 8500 lbs as towed. I installed air bags to accomodate the extra hitch weight. I have towed regular a TT before with no problems and was assured that the 5ver is a much easier tow. However, I experienced something new. A feeling the the truck was experiencing a surge from the trailer. I'm not sure how to explain. At first I thought it was the transmission shifting gears, but that proved to be not the case. It's as if the trailer is being buffeted by a regularly spaced headwind, which causes a the trailer to change its effective load on the truck. It is relatively evenly spaced phenom. Has any body had this experience, and if so, any explainations why and is there something I can do?

I just got my 5th wheel hitch installed and not had a chance to tow it yet. I will let you know if it feels any different then it did when I towed with my Dodge RAM.

Also, just curious. What is your PIN weight, and on your hitch, was it just spacers and bolts they used or did they have the long L brackets also. I wonder this because when they put my 5th wheel hitch on, the mounting kit was just the bolts and spacers and some very small 1" x 1" brackets.

[can't stop spinning]

sounds to me like your truck is way overloaded

[tedstundra]

Originally Posted by Survivor61

I just got my 5th wheel hitch installed and not had a chance to tow it yet. I will let you know if it feels any different then it did when I towed with my Dodge RAM.

Also, just curious. What is your PIN weight, and on your hitch, was it just spacers and bolts they used or did they have the long L brackets also. I wonder this because when they put my 5th wheel hitch on, the mounting kit was just the bolts and spacers and some very small 1" x 1" brackets.

The specified pin weight for this 5ver is listed at 1100 lbs., light for this much trailer. (list at 7700 lbs). Haven't actually weighed it yet so not sure of actual weight. The truck certainly handled the weight with out any problems. Pulled just fine except this funny response. One suggestion has been that I had the airbags under inflated, thus causing the the trailer to rock back and forth. That would likely give me the sensation I was experiencing. I'll try a higher setting on the bags in the future to see if that makes the feeling go away.

[notevenclose]

Sounds like the trailer brakes are grabbing more as you come to a stop.

Does your brake controller integrate the pedel pressure applied? If so, I would think the feedback you are getting from the trailer is that, as you come to a stop, you press harder on the pedel and that engages the trailer brakes harder(maybe too much harder).

If not, does the brake controller feed power to the brakes over time? As in, it takes a certain amount of time before the preset brake setting is applied to the trailer brakes?

Just throwing things out there...

[Larry]

Yesterday I towed a 4,000 pound farm tractor on my gooseneck flatbed trailer that weighs 4,400 pounds. I had plenty of power, but I felt a lot of surging. I know for a fact it is not the trailer, the brakes, or the hitch. I am wondering if I have the famous problem with the torque converter. I have some jerking when going down the road without the trailer, but I wasn't sure if it was the truck or our terrible roads. I have pulled this same trailer with my previous Ford 3/4 ton and 1 ton trucks without any problems. This heavy load seems to magnify the problem.
What exactly does the torque converter problem feel like?

[Art64]

Originally Posted by tedstundra

I just towed my new 5th wheel with my 08 SR5 4X2 for the first time. It is relatively heavy, probably around 8500 lbs as towed. I installed air bags to accomodate the extra hitch weight. I have towed regular a TT before with no problems and was assured that the 5ver is a much easier tow. However, I experienced something new. A feeling the the truck was experiencing a surge from the trailer. I'm not sure how to explain. At first I thought it was the transmission shifting gears, but that proved to be not the case. It's as if the trailer is being buffeted by a regularly spaced headwind, which causes a the trailer to change its effective load on the truck. It is relatively evenly spaced phenom. Has any body had this experience, and if so, any explainations why and is there something I can do?

You maybe experiencing "Backslap." It's like you're sitting on a chair with your back against it and somebody pulled on the chair quickly and then pushed it quickly causing your back to slap against the seat. I had a lot of this experience when I was driving 18 wheelers with leaf spring equipped trailers. If you have air bags, make sure they're not too hard or too soft. With the truck unloaded and air bags on minimum pressure, mark on the frame the top of the rear tire on both sides. This will give you the normal ride height. Then from this mark, adjust the airbags pressure accordingly once you're loaded.