Tire/towing question

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Jun 10, 2004 | 08:09 PM

SHartman

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From: outside of HoustonTX

Tire/towing question

I have a 97 PSD, LWB, SRW, automatic trans. with the camper package. My boss asked me if I would be willing to put a fifth wheel hitch on the truck so I could begin towing a 10,000 lb trailer we just acquired. I know the truck should handle the weight with no problem, but I need new tires and had been considering going up to a 285/75 from the 245's that are on there now. How would the larger tires affect the towability of this set up? Is the single rear wheels ok or should we be using a dually to pull this rig? Thanks in advance.

Jun 11, 2004 | 09:33 PM

Steina

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From: Lake Havasu City AZ

Is your boss sure about the weight of that trailer, or is it a "guesstimate"? Until you have the trailer weighed, you have no idea what you're getting into. Once you've got accurate weights of the trailer and on the hitch, then you can start planning accordingly. Good luck!!!

Steve

Jun 11, 2004 | 10:05 PM

peppy

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From: S/C Texas

Not sure if the size increase would offer more stability. It may even produce some extra roll. http://www.tirerack.com/index.jsp
I have plenty of experiance with the GoodYear Wrangler HT and I have nothing but good things to say. With 15 years fire/ems....I've abused these tires in many ways. Another good choice is the Michelin LTX A/S, which is available in load range E, gets you a couple extra belts in there. I've had these on a couple ambulances with no complaints.
My towing experience is quite limited.....but my abusive history with tires is a little lenghty.

Jun 11, 2004 | 10:31 PM

rclarke

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The 1997 towing guide lists towing capacities from 9400lbs to 14,000lbs depending on rear end ratio and body style. Oversize tires will lower the ratio of the rear end and lower the tow capacity. I also would think oversize tires might reduce the stability.

Jun 11, 2004 | 10:32 PM

SHartman

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From: outside of HoustonTX

Quote:

Originally Posted by Steina

yes I know the exact weight of the trailer, 9,987 lbs. It is a mobile air quality laboratory that I operated for the last ten years of the 30 I spent with my previous company.

I guess my question is how will the larger diameter tires affect low end torque and is the single rear wheel sufficient? I also forgot to mention the truck is an F350 with 3.55 rear gears.

Jun 12, 2004 | 12:04 AM

Steina

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From: Lake Havasu City AZ

I think the 3.55 rear gears are going to be marginal at best. Like rclarke wrote, larger diameter tires will only make it worse. Again, do you know how much weight the trailer is going to place on the hitch if you install one?

Steve

Jun 13, 2004 | 07:44 PM

rclarke

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If that truck has 3.55 gears you are going to be closer to maximun capacity than I would want to be. The 1997 Towing Guide lists 16,000lbs as gcwr and 10,500lbs as maximum tow with 4x2 and 9900lbs maximum with 4x4. I believe the weight of the truck will be over 6000lbs leaving less than 10,000lbs for any load, driver and trailer. Also the trailer at nearly 10,000lbs should have at least 2000lbs on the hitch, possibly going over the rear axle capacity.
Conclusion----I don't think you will be happy towing this heavy a load.