Originally posted by Vaughn MacKenzie
Guesterman, the 19. 5s are harder to stop because:
Larger diameter, turn slower, meaning the wheels apply more torque to the brakes which is harder to overcome.
Wheels weigh more so you have to overcome the added energy here. Which brings up another point. . . unsprung weight. I would definitely go for the aluminum wheels since the metal ones are quite heavy, 120lbs or so per wheel assy.
Vaughn
(Most of this post is addressed to Guesterman, even though I use 'you' throughout. )
I don't think my wheels weigh *quite* that much. The wheel *plus tire* may weigh close to that, but I think the tire is twice as heavy as the wheel. AndI think the weight (of mine) is closer to 100 lbs, since I can still easily pick them up.
I recently had the OEM tires on the truck for a week or three, and didn't notice any difference in stopping time/distance. But I *did* notice how mushy it felt, and could barely wait to get the 19. 5s back on!
As DOWG said, I've got the TY303 225/70/19. 5s. As to heat, I usually run 75 on the highway, year-round, conditions permitting. Unladen, the tires get warm, maybe even very warm on the hottest days. But only *once* did they get too hot to 'hold': when I had 3700 lbs. of gravel in the bed and drove, oh, 30 miles on a hot Virginia day, at under 45 MPH.
As to traction, I have no complaints with the TY303s. Running them at 65/55 front/rear PSI, they have always gripped the road, both stopping and cornering. Driving up and down VA311 between Salem and I-64, up and down mountains and around hairpin turns, I'm usually running 10-15 MPH over the cautionary speed.
Snow traction with them is also quite adequate. They aren't fantastic, because they do have the solid outer tread ribs. But I've never been stuck in snow, and they've never prevented me from traveling due to snow.
Their rain traction has been wonderful; the only time wet traction has been a problem has been on a couple roads that were oily. For instance, the left turn following US-15 north in Frederick, MD, when I slid for 50 feet due to a *lot* of oil on the pavement, and drove sideways for another 50 feet until the oil was gone.
I remarked that the tires have had somewhat less traction of late. But that is most likely because I'm running about 62 PSI in the front and about 50 in the rear, in an attempt to eliminate the odd feathering of the inner tread blocks on the front tires. But, from what I saw at Kaufmann's this past weekend, I may have discovered *why* they are feathering.
It seems that at least several different tires there would 'concave' the tread at high speed (see
http://murphy.gotourown.com/tires/tires.html for pictures. ) I *think* that's what's been happening to my tires at high speed. Up to 60 MPH or so, the tires are pretty quiet, but over that, they start singing, which is the feathering rearing it's ugly head.
But since lowering the pressure has resulted in a little less traction, I may run the pressures back up to 65/55 PSI for my upcoming trip to WI, MN, SD and IL.
As to running 245s for the added capacity, remember that the 2500 4X4 is only *rated* for about 2300 lb. payload, which might be about 3800 lbs. on the axle, or 1900 lbs. per tire. You would have to put about 8500 lbs. in the bed to load the rear tires to 5000 lbs. each.
That 5000 lbs. rating is good for highway speeds all day long, and I don't think you would be running 70 MPH for 8 hours, day in and day out with your truck *that* overloaded.
You also need to look at the weight rating of the wheels. If they're only good for 3600 lbs. , it won't make much sense to use tires that exceed that capacity.
As others have said, the 19. 5" tires are intended for vehicles with a much greater weight than our little pick-em-ups. Were I to run, say, 70 PSI in the rear tires unladen, I would be driving on only the inner tread blocks, which *greatly* reduces traction.
Unless you intend to have your truck heavily laden (to max GVW) most of the time, you should stick with 225/70-19. 5s. The TY303 tread is just as wide as the tread on the OEM 245 Goodrears.
Are the 19. 5" tires the *final* answer to all tire problems and performance requirements? No. They are, by no means, perfect, especially on our light trucks. However, considering that my truck drives and handles like a sports car with the TY303s (and KYB monotube shocks), are giving me *great* mileage, have gladly hauled the occasional almost-insane load,and give me a smoother, nicer ride than the OEM tires, I would do it again, even if I had to pay full price for the tires.
65K miles now, and I'm *still* 50K-100K miles away from needing new tires.
Fest3er
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