I think its what my setup is doing, 2004 2500hd duramax. Pulling 35 foot 311bhs keystone sprinter. Have equalizer hitch setup. I think it is setup wrong, when driving I am getting a lot of rear tow vehicle bouncing up and down, no sway just bouncing. Trailer is 8200 pounds dry. I printed instructions out off net, but I used to have hitch on f150 4x4 and just put it on other truck. Dealer set it up and I guess you have to put more washers in there somewhere, special washers or what? thanks in advance
* This post was
edited 06/14/12 06:54pm by rode2nowhere *
First you have to make sure that you don't have the dreaded quick release GMC hitch. One minute you are driving down the freeway with the trailer attached, the next it comes detached. So check carefully for cracks between where the square part meets up with the round thinwall tubing under the truck. If cracked, get rid of the 42 pound heat treated GMC hitch and install a 65 pound hitch that should have been there in the first place, with heavy duty thick wall square tubing.
Second, make sure that the hitch bars are not overtightened. If over tight, they will spring back and forth, like you mentioned in the post. You really don't need to transfer that much weight to the front axle to avoid steering issues, and the rear axle is stout enough to carry the hitch load.
Yep, sadly GM did us no favors with the hitch, you'll need to change it if it is OEM.
I had the same proposing problem from the day I bought My truck in 2005. I tried to address through WD Hitch set-up and could only get a marginal difference. I just change the shocks at 41k and solved my problem. I replaced the factory shocks with Monroe Reflex and also replaced the trailers shocks.
Now it is a smooth ride.......
2001 25dbs Tahoe TT, 2005 Chevrolet Silverado 2500 Duramax
I have an 07 Dmax with 80k on it. I replaced my shocks last week with Bilstein trying to get rid of the same thing you are. Alligator Performance has a set of 4 for $245 delivered. My old shocks could be compressed with two fingers and would not rebound when set on a work bench. They were completely shot. I haven't towed with the new shocks yet, but the truck definitely rides better. Took about 1hr to do the install with basic hand tools.
Any good hardware store should have HARDENED washers for hitch.
Usual cause is tongue weight not adjusted to be 13 to 15% of ACTUAL MEASURED FULLY LOADED TT weight, or improperly adjusted Equalizer. Often too few washers, as you suspected.
2010 Ford Expedition TV
2010 Outback 230RS Toybox, 5390# UVW, 6800# Loaded Not yet camped in Hawaii, 2 Canada Provinces, & 2 Territories I can't be lost because I don't care where this lovely road is going