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265/70 17s regular to 295/70 17s mt's on a 1500 MC-mpg/torque other worries?

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Old 02-22-2011 | 11:39 AM
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Default 265/70 17s regular to 295/70 17s mt's on a 1500 MC-mpg/torque other worries?

I have weather checking on my OE 'off-road' BF Goodrich tires for my 1500 MegaCab with 3.73 gears. I'm considering upgrading to Toyo MT 295/70s. I know they'll fit, but the quick specs indicate that I'm looking at 16lbs per tire more for this particular set-up.

What's people's experience been with similar set ups on a megacab or 2500 type axle setup as far as mileage, torque drop, premature wear, etc.

I did a search btw, but it all came up with "does it fit"- but I know it fits with no real issue. Just wondering if it's a good decision to get such an aggressive lug pattern and all the weight associated with it.
 
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Old 02-22-2011 | 12:02 PM
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I am interested in this as well. There seems to be less info on the 2500 4x4 series. I have the OE 285/70-17s BFGs on my diesel and I get 18mpg unloaded and 12 towing 8k trailer.

I was originally going to go with the same size wheel and the 295/70-17 but since then I think I've talked myself into the XD series wheel and a 295/70-18 which is a 34.4" tire. I'm worried about the tire sticking out the side of the fender well as well as it fitting without rubbing.

There are a few things to consider...+12 or -12 offsets and I think this correlates to 5.7 or 4.5 backspacing respectively...do I have that right?

Anyway don't mean to thread jack just throwing some things out there and want to see which way you go.

-E
 
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Old 02-22-2011 | 12:22 PM
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Just to clarify, 1 way or another I'm going to 285 or 295s. But there are much tamer sets of tires out there. Also, I plan to stick to the stock steel wheels.
 
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Old 02-22-2011 | 09:17 PM
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Your gas mileage will suffer, most likely in the 2-3 mpg range. The rolling resistence on a MT is much greater than a "regular" tire. To that you have the added weight and the reduction in the effective axle ratio of 6-7%. Yes, you will feel the the extra drag off the line. Everyone's tolerance to the loss of power is different. It depends on how you use your truck. Towing would not be advisable without a gear swap.

A MT was not designed to provide good tread mileage on pavement and keeping everything in balance and aligned will help. There are issues, but it will make your Megacab look alot better.
 
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Old 02-23-2011 | 12:48 PM
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Wanderer, thanks basically confirmed what I thought. As far as towing not advisable- I figured towing would still be OK, just not as much weight. I was figuring about a 5% drop in effective tow rating. Which is fine, my trailer weighs 4750 dry. It's GVWR is 7500 but full of water and stuff it was <6000 at the scales.

Anyone think the tires would make that too much of an issue? Keep in mind it's a megacab and legend says they're a little underrated because of the 2500 running gear.
 

Last edited by MrIcky; 02-23-2011 at 12:56 PM.
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Old 02-24-2011 | 02:05 PM
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The tow rating is primarily a fuction of frame. springs and tires(load range E). In my opinion, it is the strain you will put on the drive line with your gears if you have a gasser. Cannot comment if it's a diesel.
 
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Old 02-24-2011 | 09:32 PM
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Although the tires will fit (as you already know), you will definitely notice a "loss of power" due to the added rolling resistance, weight and circumference of the tire. A lower set of gears would completely take care of this issue.

You will also most likely see some additional wear to the already quick wearing ball joints and wheel bearings, although it will not be too extreme.

Lets us know which way you go, and post pics! I'm in the same boat as you... the original BFG's are ready for replacement. I will probably be going with at 285's, but would really like slightly more... just too worried about the loss of power as I don't have funds for re-gearing at the moment.
 
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Old 02-24-2011 | 09:33 PM
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Oh, and make sure you are getting load range E.
 
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Old 02-25-2011 | 02:27 PM
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They are Es. I spoke to my mechanic and decided to go for it. I'll post pics when I get them on. I don't think 285 or 295 AT's would be an issue at all. I was only worried about this particular tire because they are 72lbs each. But I only tow a trailer half a dozen times a year and it's not that heavy.
 
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Old 02-25-2011 | 04:23 PM
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i run 295-70-17's on my Megacab gasser and have a hard time getting over 10 mpg in ther winter and I don't drive it hard or fast. My buddy with a '10 F250 V10 gets better mpg! I was looking at going with 315-s but the thought of 7-8 mpg scared me away.
 


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