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Old 04-23-2007, 07:04 AM   #1
79blazer
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Red face Towing with P235/75/15

I have Mohave tires on the front and Michelin LTX M/S 235/75 SR15 105S SL on the back. They are rated about 2000 pounds at 35 PSI. Driving empty it is challenging to drive straight. It tugs randomly right or left. I Towed a 2800 pond car on a Uhaul trailer and "leaving something to be desired" is putting it mildly. It is okay at 40 MPH but it fishtails going straight with no wind at 60 mph. The back end handles so bad under load they feel like they are flat. With actual truck tires does that help much? I have a short wheel base. Well though the answer seems ovious, Better tires like Pirelli's Scorpion ATR is 2337 lbs. at 65 psi Is only 300 pounds better weight capacity than what I have now. Also gas milage is a priority. I don't drive agressivly so I don't need wide tires. I am just looking for some advice, before I spend hundreds of dollars on new tires! Would a differnt tire size help handling when towing? I don't want to have to buy new 16 inch rims if I don't have to. thanks
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Old 04-23-2007, 07:27 AM   #2
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Re: Towing with P235/75/15

My 1st guess would be the wheelbase is the route of the problems. the shorter the wheelbase the more "Squirly" it will be in all conditions.

as for the tires - I guess just use a quality 235/75R15. My buddy and I have towed regularly on all differant brands of tires in that size. Always towing a Full Open car trailer with anywhere from 2-5k on it less the trailer weight. Never a problem - towing 65-70mph.
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Old 04-23-2007, 09:03 AM   #3
Bus Ted Knuckle
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Re: Towing with P235/75/15

It probably had more to do with how you had the wieght of the vehicle distributed on the trailer. Too much or too little wieght where it needs to be will cause that squirrely feeling
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Old 04-23-2007, 12:08 PM   #4
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Re: Towing with P235/75/15

The normal "P" (passenger) rated tires are not usually rated to tow such heavy loads which might have caused some of your towing akwardness. You could always step up to an "LT" 6ply tire or a XL (extra load) "P" rated tire. With the XL tire you don't give up so much of your ride quality as you would with the heavier duty LT tire. In a lot of cases the XL tire can even handle more weight than the LT.
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Old 04-23-2007, 12:25 PM   #5
Ivan D.
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Re: Towing with P235/75/15

P235/75-15 tires do NOT belong in trucks, period, not even in half-tons. One of the truck magazines actually did a test with a late-model Ford F150 with P-rated and then LT-rated tires, don't remember what exactly the test was but the LT-rated tires just pounded over the regular passenger car ones. How important it is to have the right tires should be suggested to you by the fact my car (yes, the car, not the truck) rolls on LT235/75-15 tires, and even the spare is a LT215-75/15. My car clocks the scales at about 4250lbs with no passengers or cargo, and I don't drive fast or tow heavy stuff like you... Hell, even my 245/60-15 summer tires are the 4-ply high-load type. So yeah, switch to actual truck tires, ride change will be minor, however handling will improve greatly. That, and you know the "better safe than sorry" principle and how much trouble it saves if followed.
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Old 04-23-2007, 02:29 PM   #6
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Re: Towing with P235/75/15

Tires are one thing, but towing with a blazer just isn't going to be as stable as a LWB truck. Add to that fact if you put the car on the trailer and gave it too much tounge wieght and it makes it worse. Too much tounge wieght has the tendancy to unload the front wheels. Meaning the rear squats and the front end comes up. You don't have enough wieght on the front tires to keep them planted. It's kind of like driving a 1/2 ton truck with two tons of rocks in the bed. It will carry the load but just won't track straight.

I'm not saying towing can't be done with a Blazer, but that due to the short WB you have to pay closer attention to wieght distribution.

Heck I've towed my 69 nova on a open trailer with a 1/2 ton Z71 and the only way we could keep the front end of the truck from going sky high was to turn the car around backwards. The wieght was distributed better on the trailer and less on the tounge. The truck leveled out and pulled pretty well. Had we left with the car facing forwards it would have probably been dangerous to drive at highway speeds. That was with a longer WB truck than your Blazer too.
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Old 04-25-2007, 05:34 AM   #7
79blazer
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Re: Towing with P235/75/15

I see I should be a lot better off with real truck tires. I am thinking about putting the michelins up front and buying Pirelli
Scorpion ATR's Load range D for the back untill the michelins wear out. I would hate to waste the good michelins LTX's. Or maybe I could sell them. They have always been on the back axle, so they have exellent even tire wear. It would cost $300 total just for two tires. Pirelli
Scorpion ATR appears to be a great tire. What do you think?
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Old 04-25-2007, 09:02 AM   #8
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Re: Towing with P235/75/15

I would agree with Zoomad and Bus. Loading a trailer, even with a 3/4 or 1 ton truck can make a huge difference. While there are problems with loading the tongue too heavy, I think it is more dangerous to load the tongue too light. If you load the trailer with all of the weight on the back, it can cause the trailer to whiplash like mad at highway speeds. But you do need to get rid of those tires, or at lest stop towing until you do.
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