Need help with rim choices

[GMC69]

I've had my 1970 C20 for about 5 years now. I replaced the tires a few years ago with some Falken Ziex ST-Z04 in 245-75-16. I find that I don't get enough traction in the rear, not only in wet but also in dry. I drive it pretty normal, but once and a while do take off a bit quick.
I run 30psi in the tires.
I was thinking of going to a wider tire, but can't find what I want in a 16" to go on the rims I have already. I would like to run a 285 which would give me about 2" more in the rear, so about 11" tire.
My options are to go to an 18" rim for a tire that will match the height of my current tire and I can get the 285 width I want.

The problem is I can't decide which of the 2 rims to go with but also if I should stagger the rims. So keep a 16" up front and get the 18" for the rear. I would then only need to buy 2 rear tires. Or get 18" all around and buy 4 new tires. I barely have any mileage on the current tires.

Seeing that my truck has the black modding on it, I figured it would look good with a black with machined lip rim, but also found the same rim in just polished aluminum.

Which rim should I put on, and should I go 16/18 combo or 18" all around?

Below are the pictures of the 2 rims I would like to choose from and a couple shots of my truck. It's also on bags so one picture is fully aired up and fully down.

Truck


Up and down shot


Both rims

[Mike C]

Does your truck have a limited slip differential? That gives you 100% more traction with the tires you have.

That's easy if you have a Dana 60 but not so much with the Eaton.

My preference for wheels I think is the all polished. Obviously a tire for a performance application would have a softer rubber compound but would wear faster and not be a truck tire if you tow with yours at all anymore. And as you have found 16's are not the sweet spot for tire options anymore but the 18's are.

[GMC69]

It's an open diff. Eaton HO52. Has the 4.10 gears, so my options are limited on that front.
This truck is a summer toy and used for shows and weekend drives. I don't think I put 1,000 miles a year on it, so tires will last a while.
No towing with it either.

I originally wasn't even considering anything with black and was only looking at Chrome. But with it being 8-bolt rims and Finding a nice simple rim that suits the truck, my choice are very slim. The more I look at the black/machined rims, I think it gives it a bit more modern look, while keeping the old style of the truck.

Still undecided on going staggered 16" front 18" rear, or 18" front and rear.

[Mike C]

It's a great looking truck. A different tire might make all the difference even with the same size and rim you have.

Either way, modifications/changes to personalize the truck is what makes them so fun so go with what speaks to you!

You can find a maximum traction diff to swap in for the Eaton and that would help with some traction issues. I have not run one on the street. My experience with C20's have been Dana 60 truck with TracLoks. Which is another option if you could find a used 60 to swap.

[BugzC10]

18" front & rear...black with machined / polished lip. Maybe someone could do a rendering with both of them so you could get a better idea on the overall look. Or someone post up their truck with 18" and black look.
Nice truck BTW.

[GMC69]

Also the tires would no longer have white lettering on them. Black sidewall is what I'm finding in the size for the rear.

[GMC69]

After searching around more, looks like I can get a 275/70/16 tire. Not as wide as I would like, but wider than I have. Plus I can keep my 16" rims on it already.

I still gain a little over an inch in width and a little over 1/2" in height.

Just another option.

[GMC69]

Any suggestions on a good traction tire?

I'm not 100% set on staying 16".

Still have my options open. Even looking at 15" rims since I have a few more options for tires. I'm pretty flexible on sizes even if I loose a bit of height.

If I can find a nice wide tread pattern in whatever size rim then I can look at my wheel options then.

The current tires have a section width of 10" but a tread width of only 7.6".

I do drive in the rain with it and put maybe 1,500 miles a year on it, since I only use the truck in the summer.

[Mike C]

Tire sizes get more varied as rim size increases. IMO, the 15's give you fewer choices than the 16's, fewer than the 17's less than the 18's.

If you want asphalt traction tires, get ultra high performance summer tires. In order to get the same height you currently have which is almost 30 1/2" you need to go to the 18" rim. A 285 55 18 is the same height, of which the Pirelli Scorpion is only tire on Tirerack and is considered a all season sport truck tire. But this is probably stickier than what you are currently running.

There isn't an animal as a high performance (read sticky on the asphalt)30" + tall tire. But you can find some things in the 29" range. I have 275 55 17 on my 69 short step and you can get a 275 45 19 like Porsche runs on the Cayenne.

A limited slip doubles the amount of rubber you are driving (or cuts the load in half on each tire) and is what you need. Unfortunately that's just not a reality with the Eaton axle so a Dana swap would be in order.

How important (read how much are you willing to spin) is it to get that?

[GMC69]

I find even with an open diff, if I take off too hard, I hear both tires let go. Also my 1-2 shift, they both chirp too. When I push it, the 1-2 shift is longer than a chirp, but both tires.

I've looked at the scorpion a/tr and they look pretty good. If I loose a bit of height, no big deal. But I would have to also change the front, then again I would go to 18". I've seen the Scirpion in person on an F-150 and seem nice. Just wasn't sure how they were for traction.

[Thundarr]

How old are your tires? That model of Falken has a 460 Tread wear rating. Its already a really hard tire and could be aging on you.

I had a set of Ziex's on a Fiat Spider that was rarely driven like your truck. In 7 years and 15k miles of use, the tires looked new when I sold it. I probably never noticed traction, because it was never driven in rain and didnt really have enough power to take it to the limit of wheel slip unless I dumped the clutch.

I would say go to a tire with a lower Tread Wear rating. Based on how little you drive, I would think you could go to a 200's or 300's rated tire with plenty of life for years of use.

[Wide Open]

I like the polished wheel.
Never an easy choice. Good luck with you decision.

[GMC69]

The tires are 3 years old. Store the truck in a heated garage and if I'm not driving it, it's parked in the garage in the summer.

With the little bit of driving I do, I figured I could get away with a softer compound and still get years of use out of it.

Just looking for some brand/model of tire that might work. I'm guessing 18" rims will give me the wider tread width with a more square sidewall.

It doesn't help that my 3 year old likes it when I push the truck a bit with quicker take off or going into passing gear on the highway even if we are the only ones on the road. Won't be long and he will want the keys to the truck.