Factory Wheel/tire size question

[ian villeza]

I have a 1972 Chevy blazer and just mounted some used tires on what I believe to be original 15x7 steel rims. I went with 32x11.5x15 inch tires to see what they would look like on my stock suspension. I like the look but Hate the Performance at high speeds. My blazer starts to feel very unsteady at speeds over 55mph in the steering, Just wondering if anyone has encountered this problem. I have been told by a few tire dealers that the tires are to wide for my rims and thats why it feels scary at high speeds.
What were the factory tire/ wheel sizes? and do any of you have any recomendations.

[LUV2XCLR8]

I could be wrong, and the great thing about this board is someone else
will jump in and either correct me, agreee, or add their own $.02, but I
think factory was 15 x 6, alot of guys here on the main land run 73 up
8" rally's, personally I don't think your tires are to wide for 15 x 7's, if
you are gonna step up to something new but still want it to look stock
you can get these rally's like I pictured from my rig in a 15 x 10, hope
I answered your question, one wheel source - www.stocktonwheel.com

*My rims are 15 x 8, my tires are BFG's and are 35 x 12.5 x 15

[vtblazer]

I'd be surprised if it were the tires them self's also.

Have you had the front end up on a lift and checked over?

I've run 35x12.5's on a set of those skinny later model aluminum factory rally's and they were just fine.

Check the tires for issue's also.

On one of my trucks I have a set of LT265/75R-15's tires and they look/fit really good with a stock wheels and suspension.

[special-K]

I don`t thonk the rims are too narrow,but 8" would be mor appropriate.There were several factory sizes available:
G78-15 on 6"wheel
6.50-16 on 6"wheel
E78-15 on 6"wheel(tubeless)
G78-15 on 6" wheel(ditto)
H78....Ditto
10.00-16.5 on 8.25"wheel(tubeless)
All these were available in Highway or On-Off Road.

[ian villeza]

Thank you all for your input, I was running 31x10.5x15 inch tires and hated the look but could drive it over 70mph and it felt like a sedan. I guess running used tires is never a good Idea but I just wanted to see if they would fit before I spent $150+ per tire. I like the look of the Super Swamper TSL radials
but was wondering if I would be happier with more of a street tire since I will be cruising the streets and offroading the sand once in a while.

[vtblazer]

Originally Posted by ian villeza

I guess running used tires is never a good Idea but I just wanted to see if they would fit before I spent $150+ per tire. I like the look of the Super Swamper TSL radials

If all you did was change the tires, I'd suspect the used tires you installed to be the culprit.

I've run Super Swamper SSR's (33's & 37's) and they drive pretty nice for an off road tire. They have the 'look' IMO also.

[bouncytruck]

I'd guess it is probably the tire itself. What brand are you running? You might be getting more bump-steer from the larger tires. If so, check your rag joint, ball joints, etc. Check the tire pressure too. You may consider another brand of tire, like a BFG AT.

My '72 is running stock 16" rims with 235/85R16 (approx 31.5" tall but skinny) with a 4" lift. I don't know how wide the rims are, but I'd guess 6" or 7". It drives very nice with no bumpsteer or wandering issues. My '69 has a 6" lift with 35'x and the ride is completely different. It is a bouncy ride (my wife dubbed it "bouncytruck"). It has mimimal bumpsteer, mostly at higher speeds on the freeway.

The TSLs aren't going to be very good highway tires and probably not too great in the rain. Consider a less agressive tread.

[2wdBlazer]

I like my Parnelli Jones as a great off-road tire with excellent street manors.

Wanna talk fun to drive. Try going 75-80 on the freeway with 38's.

[mastercraftkpk]

Since the "new to you" tires are a larger size than your old tires, the difference you are feeling may be due to the new forces being exerted by the larger rolling mass of the larger tires. Even though they are just slightly larger, they may be significantly heavier and result in showing you slop in your steering/front end that you did not notice before.

If the "new" tires are properly balanced, then it's either the tires themselves, your front end/steering, or a combination of the 2.

[ian villeza]

Thank you fellow Blazer owners, Great to know your all out there with your wealth of knowledge and wisdom. I may have overstated my steering issues and just needed to get used to the feel of these different size tires. I am not happy with my 32's and want to go bigger! Unfortuanetly here in Hawaii anything over stock requires a reconstruction certificate. I'm guessing that 33's will still not satisfy my wanting to go "BIG". I'm sure a Lift is Coming in the near future so I can run even bigger tires than the 33's I'm Looking to try next. Here's a pic of my 72 in primer, I managed to do a horrible spray job on Sunday, with a ton of overspray but at least I'm one color on the exterior now.

[LUV2XCLR8]

Looks pretty good to me, wonder how many of those things originally went to HAWAII

[3 on the tree]

My glovebox sticker shows 2 codes for tires, I am confused. One shows G78 15, and another code shows 825 X 15. Why 2 different codes???

[special-K]

Originally Posted by 3 on the tree

My glovebox sticker shows 2 codes for tires, I am confused. One shows G78 15, and another code shows 825 X 15. Why 2 different codes???

Good question,you got me!Drinking on the job?herbal essence??both???

[bouncytruck]

Take a few weeks to get the feel of the new tires. It still may be issue of the tires. There is something to be said about quality tires.

If you go with bigger tires, it isn't recommended that you run greater than 35's on the 1/2 ton running gear. That being said, there are several board members who have run much larger tires on the 1/2 ton gear without many problems. A lot depends on your driving style. I'd guess your rig has either 3.07 gear or 3.73. The 3.73 will be ok for 35" tires, but 4.10 would be better. If you go bigger, you will definately want to swap gears.