piac
long island
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what is better and safer to tow with? stock 265/70r17 113s maxload of 2535 or 275/55/20 117h with a maxload of 2833 and why?
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skipnchar
Topeka Kansas USA
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Joined: 12/17/2003
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Wheel diameter has nothing to do with EASE or SAFETY while towing. Either size can be equally good for towing but....if you CHANGE to larger wheels without changing the gearing in the differential you will be raising your gear ration and robbing your tow vehicle of power you MAY need for towing. If you change to a SMALLER wheel size you'll be doing the opposite and lowering the gear ratio effectively and increasing the power to the wheels.
2004 F-250 SCREW Long Bed (new)
OR 2004 F-150 HD (85,000 towing miles)
Rockwood 8314SS 34' travel trailer
We have enough YOUTH...how about a fountain of SMART
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piac
long island
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Thanks for that reply skipnchar, But I am getting confusing results while researching this...some say you lose towing capacity by going with the 20's, but in fact the only difference is in weight, not circumference, so the ratio shouldnt change. others say the 20's arent rated for towing yet all of the load ratings for them are higher. I actually have both sets, the original 17s and the new 20s. reason for my question is i am getting a new tt. my old tt was 5600lbs and my yukon xl with the 20s pulled it no problem...the new tt is 6600lbs so I am just wondering if i should go back to the original 17s????
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smkettner
Southern California
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Joined: 03/21/2005
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I know you can get an LT265/70R17-C or E
Can you get an LT275/55/20 ?
I see you posted load ratings of the tires? Check the wheel ratings also.
Tires of the same height will not alter the gearing.
* This post was
edited 10/25/09 01:08pm by smkettner *
2001 F150 SuperCrew
2006 Keystone Springdale 249FWBHLS
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johnrbd
Hanford CA
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So your 20" tires must be lower profile than 17's? Duh, obviously, just reread your post.
What engine and rear end are you running?
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piac
long island
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Look johnrbd Dont be a SA...when you upgrade the tire size, if you do it right that is, the overall circumference stays the same...2002 yukon xl denali, 6.0 awd
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Road Ruler
Canada
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Joined: 09/11/2003
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"Generally speaking" lower profile tires will have less side play (wobble) than a higher profile tire (with the same ratings).
Less side play is a good thing when towing.
Airstreams.... the best towing trailers on the planet!
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five'er
Canada
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I have 20's on my truck and I know from my research that the tow rating drops for having 20's. The reason is because there is LESS sidewall and therefore less ability to absorb shock and therefore a greater risk of damaging the tire and wheel. That is what I found when I searched for reasons.. perhaps there are others.
2009 1500 Dodge Sport QC, Prodigy Brake Controller, 2009 KZ 266 MXT
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BenK
SF BayArea
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Joined: 04/18/2002
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Kinda sorta yes and no...
Same weight carry rating will have the larger dia wheel weigh more, lots
more. Meaning more unsprung weight. More centrifugal forces both to get
it going and to stop it (fly wheel). This will require more HP to get
it going and more braking forces to stop it...than a smaller dia wheel
Assuming these wheels are rated 3,000 lbs or more, right?
If the tire OD is the same/similar, the diff ratio will not change, or
only change by the same percentage the tire OD changes from OEM OD.
Lower sidewall profile (aspect ratio, or that center number...like in
265/75R16...that 75 is 75% of the width...265mm). Lower profile will
less sidewall flexing and a good thing for anything to do with handling,
but the down side is stiffer and the ride quality goes down.
With a lower aspect ratio and wider tread, there is a greater change
of hydroplaning on wet pavement. Speed a key component along with
PSI on pavement (how wide the tire is).
Also, with a lower aspect ration and the wider the tire, the harder it
is for the designers/engineers to keep the center of the tread from
ballooning. Especially in higher ply ratings, as the PSI goes up with
that increase in weight carry capacity. Why 'most' low profile tires
with high ply ratings will have lower PSI than the same rated tire
but with a higher aspect ratio.
Careful. Too many larger dia wheels are for the fashion statement
crowd who don't tow heavy or use LT tires. They usually have a lower
weight rating than a smaller dia wheel. Also, this crowd usually
don't understand the difference between a 'P' rated tire and the next
higher class tire, 'LT', which has higher PSI requirements and
therefore the valve stem must also be of a higher class
I also off road and won't touch anything larger than a 16" dia wheel
and 75 aspect ratio 'LT' tires. My serious off road set of tires and
wheels are OEM steel with LT235/85R16E's and next set looking at
LT245/85R16E's or LT255/85R16E's (think they are available now).
-Ben Picture of my rig
1996 GMC SLT Suburban 3/4 ton K3500/7.4L/4:1/+150Kmiles orig owner...
1980 Chevy Silverado C10/long bed/"BUILT" 5.7L/3:73/1 ton helper springs/+329Kmiles, bought it from dad...
1998 Mazda B2500 (1/2 ton) pickup, 2nd owner...
Praise Dyno Brake equiped and all have "nose bleed" braking!
Previous trucks/offroaders: 40's Jeep restored in mid 60's / 69 DuneBuggy (approx +1K lb: VW pan/200hpCorvair: eng, cam, dual carb'w velocity stacks'n 18" runners, 4spd transaxle) made myself from ground up / 1970 Toyota FJ40 / 1973 K5 Blazer (2dr Tahoe, 1 ton axles front/rear, +255K miles when sold it)...
Sold the boat (looking for another): Trophy with twin 150's...
51 cylinders in household, what's yours?...
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Rockiesview
Western Colo.
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Since you have both sets of tire/wheels, try one and then the other and get back to us with a report.
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