Towing Report- 1991 Suburban and 32 foot camper
I have finally taken my camper out for the first time with my 1991 Suburban from December 26-30. I'm sorry it's taken me this long to report, but I've been busy trying to get projects done on my vacation before I go back to work.
The tow vehicle was my beloved 1991 Chevy Suburban that I've converted from a 1/2 ton truck to a 3/4 ton truck complete with a 14-bolt full floating rear axle, 3/4 ton front control arms and spindles, Firestone airbags on the rear springs, a massive transmission cooler, external transmission filter, and deep transmission pan with trans temp sender in it. I've got more mods done to the truck, but those are all the ones I think are relevant to towing. I also have a cheap towmaster brake controller to handle the trailer brakes.
The camper is a 32 foot camper that weighs about 9500 pounds with no water in the tank. According to the date plate, a full tank of water would add another 380 pounds to it.
I hooked the camper up to the truck and set my weight distributing hitch to 5 links hanging. The trailer was sitting level and the front fender clearance to the ground was about 1" higher than it started unloaded. I then aired up the airbags in the rear until I reached approximately the unloaded ride height. Hooked up chains and trailer lights, and tested them. Bad connection at the trailer light connector, but that was easily remedied with a screwdriver moving a prong on the trailer side. Pre-tripping the rest of the truck revealed I had virtually no transmission fluid. Pretty big issue. Luckily I had some to put in and filled it up. Now, my transmission has had a history of leaking and I used up the last of the ATF I had, so I stopped at the parts store on the way out. There, I looked under the truck and found I had a pretty good ATF drip coming from a cooler line. After spending 45 minutes fiddling with the hose clamp to tighten it, I refilled the transmission and continued on my way.
The engine and transmission knew the trailer was there, but didn't show any signs of distress. Engine coolant was normal at around 190F and the transmission temperature was no higher than 150F. I attribute these abnormally low temperatures to the cool ambient temperature; my transmission usually runs at 175F when cruising at 70mph in overdrive. I had the transmission locked into 3rd since towing in overdrive is a big no-no.
I was only able to do 45-48mph on the way out. The wind was pretty strong and whenever I'd try to go any faster, the sway of the trailer got to the point that I didn't feel safe. On the way home, I was able to make 55mph pretty easily, bursting up to 60 and even 65mph. At these speeds, I was running 2500rpm pretty much the whole time. Since this was my first time towing the camper and being the biggest thing I've towed, I took it easy and made sure to swing wide and give myself plenty of clearance at the tail of the trailer.
Feeling good, I stopped at a local truck stop and scaled the truck and trailer both with and without the weight distributing hitch bars hooked and unhooked and just the truck. Here's the results of that; all numbers are in pounds:
|Trailer w/weight bars unhooked
|Trailer w/weight bars hooked
So, referring to the table, I only transferred 100 pounds onto the steer axle...not enough. So, I think next time I'll add another link or possibly even 2 to the weight distributing bars to try to get some more load on the steer axle. When I weighed the truck, I didn't have any water in my fresh water tank or a full tank of fuel, so I think with both, I'll be close to 16000 pounds gross.
Fuel economy was interesting. Unloaded, I can average 15mpg. With the trailer, I calculated I only made 8.5mpg. Horrifying by itself, but considering the load and lack of aerodynamics, I think I did pretty well. I'm going to try to gain some mpg with a couple mods including upgrading the ignition with a hotter coil and bumping up the timing, an e-fan install, and a couple of other things. I am also planning on replacing the rubber hose and hose clamps for the transmission cooler setup with stainless braided hoses with the good fittings on the end to try to reduce the possibility of leaks like the loose hose clamp I had.
I think I covered everything I wanted to. If ya'll have any questions, I'll be more than happy to answer them as best I can. So, here's a couple pics:
This pic was before I added air to the airbags. The back of the suburban was a little higher than that when I towed it
The camper setup at the campsite