The Stovebolt Site Forums The Shop Area General Truck Talk bias versus radials (again)

Anyone who has been interested enough to follow my problems with choosing a tire will know this story.

Basically I have bias ply tires on the 49 and love them except they are at least 10 years old and have good tread and sidewall, but are out of round. I have followed all the posts extolling the virtues and liabilities of both types and of course I am confused (or is that undecided).

To make matters worse I ran into two Corvette owners, one a 1958 and the other a 1960, and both are running BFG bias-ply tires and love them. They had both tried radial and were not happy. Seems these do not flat spot and run smooth. They highly recommended I stay with bias types.

Of course my stock old 49 is not a Corvette and won't handle quite the same. But I don't drive freeways, seldom go above 50 and drive about 2500 miles per year. I don't carry any loads either.


I did have radial tires on my 53 and they were okay but I did not find them any smoother than my bias ply.

I think my old tires are nylon and the newer bias types are poly - something which might tell me why they do not flat spot.


Anyway I am still debating it in my mind and I know what bias tires are like on this truck and putting on radials is, to me, an unknown even some people love them.

I asked about this subject in another thread a while back. Its my opinon that radials may not work well on the older trucks. The system used for ride control on the AD trucks was crude at best. I feel that the radial may try and over correct as its only part of the supension. On a modern truck the radials work with shocks springs and other parts that arent there and sometime wouldn't have existed on the older ones. I've been told many times that worn front tires are not only caused by poor alginment but also poor shocks and worn springs. Giving this it stands to reason that the radial may not be the thing to put on, at least not without tuning up the other parts. This is my nickels worth.

i have had radials on my 54 since i got in 83 and it is the only way to go. ron

i have had radials on my 54 since i got it in 83 and it is the only way to go. ron

the single most important thing about the switch is that most folks use car radials with soft side walls, wide tread, and lower profile - find some truck radials the appropriate height with tread as narrow as the bias and you'll love'em, not to mention be safer and improve mileage - can't get sizes narrow enough for a Vette

Bill

Ok, I want to know more. Never heard of a "truck radial". Are you talking about a tire with more than a 4ply rating? The skys pretty much the limit on how many plys you can have, but then you quickly give up a smooth ride and are back to square one. I've seen 6.00x 15 and 16, in bias but not in a radial.

LTR = truck radials, yes, have a higher load rating - I've got 700x15LTR's from Yokohama - they're 10 ply so a bit "harsher", but I don't expect a truck to ride like a caddy, I want one that handles well, doesn't eat front bearings, and hauls a load, all really controlled by suspension as much or more than tires - if you want car soft ride, convert to modern car suspension - don't mind the thumpin caused by bias tires gettin flat spots sitting, and getting much less life from the going out of round from those flats bumpin along, like olblu's problem, stick with bias for the original look

the object of radials isn't plush ride, it's safety, traction, and mileage, both gas mileage and tire life - and note especially that narrower tread means less danger of hydroplaneing - any size radial is available if you look around, tho maybe not at yer corner walmart - if you want softer, don't care about tread width shortening front suspension component life, get Pmetric sizes, like come on new trucks

Bill

The tires I was going to buy were Uniroyal Laredo LT 215-85R16. These are commonly used on dualies. The two Corvette owners I spoke with both independantly claimed they had no flat spotting after even weeks of the car sitting idle. As I wrote above maybe it is the rubber compound they now use. My coopers are nylon and the bias ply shown in the Coker catalog, for example say they are "poly" whatever that is.

Bill, what truck are you running these tires on? I ussally run 6plys on my trucks, but have run a 10 ply before. I didnt care for the sharp ride of the heavy tire. Be interesting to compare the ride of the differnt types on a given truck. The front axil is the place where I feel these radials wouldnt be good. You would have to make sure that all the other things like king pins, shocks, and spring pins/bushing where up to snuff. I'm not oppossed to using the radial tire, just havent seen one or a combination that I thought would work out right.

Jeff, it is a stock 49 Chevy half ton. There is a bit of play in the king pins but not dangerously so. The roller wheel bearings are perfect and the tie rod/drag links are good. The lever/arm front shocks have been replaced with tubular. I don't carry any major weight in the back and normally drive city streets and country roads. Very seldom on a freeway or at high speeds.
As mentioned I had radials on my 53 and they were okay but the bias ply I have on the 49 run really nice except at 45 mph when I feel the out of round.

I have three 1/2 ton '54 trucks with radial tires and they all drive very nicely.

Two of the trucks have old front ends (not restored) and one has a restored front end.

TOYO 8 ply Hyparadial ST
70R15 LT (with tubes, on original 15" rims)

Bridgestone 4 ply Dueler H/T
P215/70R16 (tubeless, on original 16" rims)
(this is a wider profile, car tire, but looks OK)

Cooper 4 ply SRM II
LT215/85R16 (with tubes, on original 16" rims)

These are all blackwalls (the Cooper & Toyo look like truck tires) and they all wander less than any bias truck tires that I have have used.

Tim

oldblu49 - I struggled with the decison for a long time. I don't know what your overall goal is but I chose bias ply for the following reasons:

1) I have a side-mount spare carrier and wanted assurance that my spare would fit the fender cutout correctly.
2) I didn't want to risk front end clearance issues with a wider tire. (I'm a restorer rather than an experimenter or a tinkerer)
3) My truck is an antique and I want antique look as much as possible.
4) Don't like lowered trucks.
5) Old trucks don't look like old trucks with radials on them.

I have been following this post closely because I am in the same vote, do I go with bias or radials.

I agree with you Mike but I can't justify $225.00 (can.) a piece for original bias tires at this time. So I am looking for a tire that has an antique look like the original bias.

There's got to be one out there. Any suggestions?

Rob

Bought my first set of radials in 1968. Since then, have purchased only 1 set of bias-ply tires - for a numbers matching show car.

Suggestion - if going radials, don't try to beat the price by ordering mail-order, or whats on sale. Talk to an older gentleman at a local tire shop, and see what they reccomend; then ask if these will be going on sale any time soon. Getting the tire correct for the application is important.

My own personal experience is that radials will give 15~40 percent better fuel economy, and outlast 3 to 5 sets of bias-ply tires. Others may have differing experiences.

Jon.

I am not trying to change anyone's mind but here are some answers to concerns stated above:

All tire suppliers should have tire dimension information available, including inflated and loaded diameters.

There would be no front clearance problems with correct-sized tires on an original truck.

I would be willing to bet that a person could not tell if a narrow, high-profile, LT radial tire was radial or bias from 20 or more feet away (for example, the commonly available LT215/85R16 blackwall LT radial tire on a stock/standard wheel.

I don't either, but this does not seem related to the question about radial tires? The LT215/85R16 is a little larger diameter that the stock 15"/16"" tires.

People regularly ask me if it is hard to get old style tires for my trucks and are surprised when I tell them I have radials.

By the way, Coker Tires supposedly has a blackwall radial tire that was designed to match the appearance of a 6.50x16 bias tire (but it isn't cheap).

Tim

Mike, (50GMC253)there is no real goal. I've had this truck for a very long time. It is old, has scratches, paint blemishes and is missing half a headliner. The drive line is almost totally redone and it runs beautifully. I do not want a show truck (been there) or even a fancy eye catcher. I just want an old nearly stock/original
truck that I can drive anywhere anytime with out worrying about it or what someone might say because it has paint chips. A driver!

oldblu49,
Sounds like you and I are very similar in our vintage truck demands. My '50 is cute and all scratched up but it purrs like a dallas cheerleader.

I had bias on for over 20+ years and just recently went to radials because the old bias were so cracked, it started to freak me out.

Wished I went radial years ago. The truck drives so much smoother and better. No longer are the tires looking for grooves in the highways (groove finders).

I would only stay with bias if I was going concourse...........................

Craig

So many pros and cons. The only thing I should do is try both ways. Bias ply tires will cost me $600 and radials, including wider rims, will be about $1200. A lot to pay for an experiment. On the other had a friend has a 51 with radials/tubes on his stock rims and maybe I should take half a day and swap them to see. He only has about 5 miles on the tires but he put them on about 2 years ago.

I run 215-85R16's on my '50 with stock 16" rims without tubes. They hold air fine and I do not have any clearance issues. The difference between these and the bias ply I used to run was dramatic in my opinion. I especially like not having unscheduled lane changes on grooved pavement.
Steve O

I got Coker Classics Wide whites on my 52 and I can't get over 55 or they shake my teeth out....

oldblu49, here is some more information for you.

Radial vs Bias ply

Scroll down and check out the animation and you will see what happens under load conditions.

When I bought Number Seven, the tires that were on there were the normal assortment of varied sizes that is typical of a farm beater. They were all bias ply, and they were older than dirt. There were two 7.00x15's, a 7.50x15, a 9.25x15 and the spare was another 7.50x15.

We figured that since the 9.25x15 worked on the stock rims, we could get away with the 235/75R15's -- which are about twenty thousandths wider on the tread than the 9.25x15's.

They work like champs. They mounted up great, and they ride really nice. I haven't gotten to drive it much, so I can't weigh in on the gas mileage issue, but you really DON'T need to buy new rims, especially if you're looking at something like a 215/85R16's.

COSMO - the wider rim story is a result of my tire dealer(s) refusing to use the stock rims because of safety. He says (and I've read it) that the 215-85R16 needs at least a 5.5" wide rim. He would put them on if I insisted but would not warrant them nor would the manufacturer and because the rim is narrow the sidewall would bulge more than normal and it would be riding high on the crown of the tire. Believe me I'd love to use my stock rims.
Bill

Hey guys, I'm new here, but I can shed some light
on the situation. I work at a tire shop and would
definetly suggest radials, especially if your truck is going to see a lot of miles. I have
30x9.50x15's on my '55 3200 and I love 'em.
Oh, by the way, 215-85-16 should fine on a stock
rim, Ford used a 5.5 rim up into the early '80s.
I've mounted tires wider than that on them with
no problems. Just make sure to keep the inflation
correct and rotate rugularly.

Well, I've put about 150 miles on the 215-85R-16 tires I just had installed on my original 16" rims, and I'd never go back to bias ply tires. The ride and handling is better and slightly quieter, There doesn't seem to be any downside to the change except possibly for slightly slower steering. Effort is a little less though.

Nowdays, any business that deals with a product that has any possibility of causing harm to property or personal injury has to be careful. There are scads of lawyers out there willing to help some one find the nearest deep pockets if an accident occurs.

I'll tell ya though, you won't have any problems mounting radials on your original rims as long as you don't try to run the Daytona 500 or something with them. The performance envelope of these old trucks in stock form just ain't gonna stress those tires.
My two bits

Saw a late 40s Ford half ton with 650-16 Coker radial tires. They are on stock 4.5 rims. He was also told by the dealer they could/would not put 215-85R16 on his rims. That's the fourth in the area.
However the Coker tires cost him $256 each plus $20 each for shipping plus 14% tax and then installation and balance.
Now you might know why I posted this topic. That is a lot of money to use to experiment with tire choices.

Sounds like you have a really anal dealer over there on the Island, olblu. So, let's see - a 29" high 6.50-16 Coker tire is OK an a 4.5" Ford rim, but a 29" high 215-85R-16 Cooper or Goodyear LT truck radial on a 5" wide Chevy rim is dangerous. Hmmmm. I'd look for another dealer - do you have anyone selling Cooper Traveller tires over there?

Fred that makes 4 dealers! As for Cooper there is nothing nearby I don't believe. The Chevy rim is 4.5" is it not?
And the 650-16 Coker is a radial, that's how they classify it using the old bias numbers.

I just put new wheels and radials on my truck. I wish I would have done it a long time ago. The improvement is absolutely remarkable! A MUCH, MUCH smoother ride, better handling, and easier to steer. With my new O.D., my truck is capable of 85 mph. Driving at that speed with the old set was down right scary. Now it handles just like a new truck at that speed. At 75 mph the ride is amazingly smooth and quiet. I had 15" split rims w/ 7.00 x 15" tires and tubes. Now I have 16" wheels w/p235 75r16s. They are made by Continental and were recommended by some local guys I know that are into racing. My wheels are original centers with new outers. I am using my original hubcaps and I like the look very much. http://community.webshots.com/mypho...mp;albumID=551767449&security=ItqmWh

I too am a huge believer in radial tires. My bias ply were way out of round and there are several times in the year that my truck sits idle in my garage. This would create flat spots but having the radials takes this issue away.

My truck handles 200% better and I too have had my truck up to around 85 mph screaming through the Fort McHenry tunnel during the ATHS national show. I would have never made it past 55 on the bias tires.....

I put radials on my '66. I love the crap out of them compared to bias tires. I bought a set of 235/75R15's and had them put on the stock 15x6 rims and they did fine. I later swaped them to a set of 15x8 rims and the ride and handling is better yet. I'm hooked on radials.