Tire sizes - 275/60r15 rear - fronts 235/70r15 OR 255/60r15???

[Chuck78]

I am torn between tire selection coices looking for some input. I use my truck for hauling medium loads and once in a great while, pulling a trailer. Load ratings are critical for me, but so is a good handling tire. Shorter tread life expectancy is a bonus for me as that means better road grip.

I got a set of four 5 lug 5" b.c. American Racing Torque Thrust 15x8's with 275/60r15 Firestone Firehawk Indy 500's on them - I will use the 275/60r15's only on the rear.

I'm very pleased with the look, load capacity (2174lbs?), and road grip of the rears on my redrilled Dana 44 axles. On the front, I have some late 70's Blazer (so I am told) aluminum 15x7 6 lug wheels for now until I swap the 73-91 Suburban disc brake front end.


NOW...
On the fronts, I'm looking at either a 235/70r15 OR a 255/60r15.
I have ooollldddddddd G60-15's on it now, basically a 245/60-15. They have a great width, but the 25" diameter looks slightly too small in the big fenderwells. I had to lower the torsion bar suspension ride height to make them look somewhat acceptable.


Pros/Cons:

235/70r15
*1,929lbs load rating - slightly higher than the 255/60 - this panel truck has a monstrously heavy 800 lb GMC big block v6.
*fills up the fenderwell better, 28" height matches the 28.1" of the rear
*28" height will give slightly better ground clearance by 1/2" - heavy engine may need extra suspension travel
*narrower - will get more bite per square inch on wet roads, more sidewall squirm/flex in corners however
*narrower - if I keep the manual steering, 235 will be slightly more manageable parallel parking etc.
*narrower - these may not look as good on a 15x8 rim when I swap to the 5 lug disc brake front end. They are an acceptable fit on an 8" rim however, per manufacturer.


255/60r15
*1,874lbs load rating - less than the 235/70 but not by much - 54lbs less per ft tire
**255 wider width will definitely make it handle better on windy roads and turns. I do greatly enjoy a sporty ride, getting better handling in curves on my light hauler truck would be a bonus
**27.1" overall height makes the 60 series sidewall 1/2" shorter than the 235/70 - this tire will definitely squirm less in the turns, giving it better handling. With a monster 800 lb GMC big block v6 engine, the squirm may be even more than average - the 255/60 will be a big plus for the sporty ride factor
*?*will a 27.1" height still look too small in this big 60-66 front fenderwell??? The 26" 245/60-15 looks too small for a truck. 28" looks great
*255 width will get better grip on dry pavement but slightly less on wet pavement. Will the extra grippy Maxxis tread compound, massive weight of the GMC big block v6, & the Vee type directional tread pattern make up for the extra width in terms of wet pavement traction?
*255 width will look more squared off and proper when mounted on the 15x8 5 lug wheels that I plan to swap when I do the 1989 Suburban 5 lug disc brake crossmember swap.


Photos later, I have to air up the dry rotted front tires when I get home.

[Chuck78]

These Firestone Firehawk Indy 500's were previously the single best affordable choice in raised white letter 14&15" musclecar tires, as they were the only ones that had above average construction and grip compared to the rest of the RWL "cosmetic performance tires." Major bummer, the new version Wide Oval Indy 500's are only available in 16" & up.

My choices have been narrowed down to the Cooper Cobra (same tire as Mickey Thompson Sportsman S/T but cheaper $), basically not much better than the $$$ BFG TA Radials that I was just "ok" with (the Indy 500's gripped/cornered substantially better on an aggressively driven pro-touring 70-81 Camaro/Firebird platform).
The other choice is the MAXXIS Marauder MA-S1. This is a light truck/SUV tire that has become the popular underdog in the musclecar / pro-touring crowd for car use, as it is one of the few quality constructed H-speed-rated soft grippy tires left available in a 15". The V directional tread pattern some complain about being noisy, but for the grip/construction and price, I will deal with that to give it a shot.





https://www.youtube.com/watch?v=DeabcdD5Gzo

http://www.maxxis.com/catalog/tire-8...er-ma-s1#sizes

http://www.onlinetires.com/products/...uder+102h.html

The other promising leads turned out to be AWESOME for a sporty middleweight musclecar (Camaro/Mustang), the very grippy high performance Hoosier street Radial and the Mickey Thompson Sportsman S/R (2x the $ of the $100 Cooper Cobra which is same tire as the $140 Mickey Thompson Sportsman S / T ). The letdown was that these are performance car tires designed for those types of cars, hence lower load ratings of 1400-1600lbs. Deal breaker.

[Chuck78]

EDIT - the current G60-15's are 26.1" diameter, NOT 25" as I stated in 1st post. Missed my time frame to edit that. The 26" tires look too small. 28" is plenty. Will the 27" look adequate? They will surely give it a more sporty feel over the 28" 235/70.

[Chevy Fleetside]

255/60/15 up front 275's rear. I'm running a 454 BB. Handles fine. I have put some loads in it but not real heavy. I went with the Mickey Thompsons just to be different. I ordered them from Summit Racing plus I got summit bucks with them which I applied to when I ordered my rims. I think if you have a 70 series tire mixed with a 60's series tire it might look odd.

[Slow Build]

I have had 235/70/15 on 7" front with 275/60/15 on 8" rear on a newer truck. I didn't like the look of it. I don't know if it was an optical allusion but it looked like the front tires were taller than the rears even though they were the same diameter. I would go with the 255/60/15's for sure.

[forestb]

I wouldn't go with anything smaller in diameter than the 275/60R15's in the front. I did a while back ago and always thought it looked to small in the wheel well.

[forestb]

Here is a photo

[Chuck78]

Originally Posted by Chevy Fleetside

255/60/15 up front 275's rear.

I think if you have a 70 series tire mixed with a 60's series tire it might look odd.

I think with a 60 series 245 up front on mine, it looks really odd, even after I lowered the front suspension (torsion bars, adjusts with the crank of a ratchet) quite a bit lower...

The 275/60 & 235/70 have nearly the exact same sidewall height. Guys with 275/60's on musclecars have complained on forums that the rear squirms as if it's riding on balloons, however. Mine seem to look pretty correct aesthetically on the rear.
The front wheelwells are much larger and more open than the rears, and my 245/60R15's at 26" tall look anemic compared to the 28" tall 275/60 rears.

I was afraid the 255/60R15 would still look too tiny. I know it will give the better steering response and dry grip. The 235/70 will give better wet grip and ride height. I'm still not convinced that it won't fill the wheel well better / more appropriately than the 255/60R15... I'll have to stare at your photo some more, Chevy Fleetside.

[Chuck78]

Originally Posted by forestb

I wouldn't go with anything smaller in diameter than the 275/60R15's in the front. I did a while back ago and always thought it looked to small in the wheel well.

Pardon the rust!




28" tall 275/60R15 in rear. Looks perfect in my opinion.


26" tall 245/60R15 in front, front suspension lowered 2" or more to offset the small tire.


I think I will really like the better filled wheelwell look of the 28" 235/70R15, but I know I will like the handling of the 255/60R15 better.
The extra ground clearance and suspension travel with the 28" 235/70R15 will be a bonus for hauling/towing for me however (look at rockers, truck body is pitched forward - lower in the front currently - would be nice to level it back out slightly).

[Chevy Fleetside]

Here is a different angle for you. Different lighting also. My truck is lowered 3" up front and 4 on the rear. I am thinking about putting 3" drop springs in the rear instead of 4".

[suburban99]

255 fronts and 275 rears...15x8 wheels.