Tire Purchase - Bias/Radial

P

Paul Bennett

Well-known member
50 Merc awaits wheel alignment (2 weeks) after replacing the rebuilt steering box. My G78-15 tires are tired (78-15 is normal size per manual).

Nearby tire shops are useless for information ... typical - they never heard of Coker or even "what's a bias ply tire?"

Important Information Needed - Questions:
1. Will original wheels hold radial air without sealing?
2. Apart from better mileage, is there any steering advantage bias vs radial?
3. One shop wants $150 to mount-balance for 4 tires I carry in. Normal?
4. What size for daily driver?
5. Where to buy for best warranty (assuming a universal price)?
 
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#2 - I couldn't believe the difference when I went to radials. No wandering you get with bias and better control with a road that has grooves that run with the road. There was a spot in town that tractor trailers had caused deep depressions in the blacktop from stopping at a light. Those depressions always steered my car L & R. Radials solved that.
 
Yes, the wheels will accept 215/75R15 radial tires (without any special "sealing") which are a replacement for the original 7:10-15 (normal) bias ply tires.
 
#1. - I put a set of Coker Classic tubeless radials on the stock wheels on my '51 Ford; no leaks.
#2. - I agree completely with "fordor41".
#3. - I think that's outrageous, but it's common; they really don't want to mount your tires, they want to sell you some. I bought a $89.95 tire machine from Northern Tool. It took some modification before it would work properly, but now I'm sure glad I have it (so are my friends). I know good used pro machines are supposed to be all over Craigs List, but I'll be damned if I can find them.
#4. - I put 185R75X15's on the front of my '51 Ford and 225R75X15's on the rear. I love 'em (and "rubber rakes"). The Merc would probably work better with one size bigger tires. It seems that 205R75X15 tires are like vodka; they go with anything.
#5. - Can't help ya' here. I bought the Coker Classics because Coker is a H.A.M.B. Alliance vendor with all that entails.
 
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the shop near me charges 10.00 to mount and balance tires. took 4 loose tires and 4 old tires on rims last month 40.00. i did have to take my old tires or pay an extra 20.00 for him to dispose of.
 
tubman said:
#1. - I put a set of Coker Classic tubeless radials on the stock wheels on my '51 Ford; no leaks.
#2. - I agree completely with "fordor41".
#3. - I think that's outrageous, but it's common; they really don't want to mount your tires, they want to sell you some. I bought a $89.95 tire machine from Northern Tool. It took some modification before it would work properly, but now I'm sure glad I have it (so are my friends). I know good used pro machines are supposed to be all over Craigs List, but I'll be damned if I can find them.
#4. - I put 185R75X15's on the front of my '51 Ford and 225R75X15's on the rear. I love 'em (and "rubber rakes"). The Merc would probably work better with one size bigger tires. It seems that 205R75X15 tires are like vodka; they go with anything.
#5. - Can't help ya' here. I bought the Coker Classics because Coker is a H.A.M.B. Alliance vendor with all that entails.
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What tire pressure are you using?
 
32 psi because that's what it says on the tire. That's what I started with and everything seems fine, so I see no need to experiment, You do have me thinking now, however. Thanks a lot.:confused:
 
tubman said:
32 psi because that's what it says on the tire. That's what I started with and everything seems fine, so I see no need to experiment, You do have me thinking now, however. Thanks a lot.:confused:
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The pressure shown on the sidewall is generally the pressure at which the load rating is specified and doesn't necessarily relate to any particular vehicle on which the tire could be mounted. Experimenting with different pressures could yield some benefits.

Bob
 
Hi Paul...............running 205/60R15 front---205/75R15 back. Radials only way to go for daily driver as far as I am concerned. Running 34lbs pressure.
 
Tire pressures depend on the type of tire and the load range it will be hauling. 30 to 35 psi is average for passenger cars depending on load.
 
rotorwrench said:
Tire pressures depend on the type of tire and the load range it will be hauling. 30 to 35 psi is average for passenger cars depending on load.
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This is for radials. Bias plies run a lower pressure. I think the owners manual for my '51 specifies 26-28 psi. Generally, the car companies specify a lower pressure (for a more comfortable ride) than the tire companies (who are looking for maximum tread life).
 
Most I have had to pay to have tires mounted/balanced is $20 per tire. They will charge you for tire disposal if you don't take the old tires with you.
 
We can take either 5 or 10 tires (can't remember for sure which) per week to be disposed of W/O a charge, more than that is $2.00 per tire I think.
 
I am running Coker Classic Tires P225/75R15 tubeless, all around on my 53' Merc. The tire pressure is 31psi (the label that came on the tires say "inflate at 35 PSI") and you can still feel every expansion crack in the road. It handles great in the rain and dry road conditions.
 
If you want wide whites, Coker and Diamond back are about the only choices that I know.


Ii prefer the Diamond Back's, lots of controversy on Cokers. Got Diamond Backs on my Tbird, but not a lot of miles on them yet.
 
marko39 said:
the shop near me charges 10.00 to mount and balance tires. took 4 loose tires and 4 old tires on rims last month 40.00. i did have to take my old tires or pay an extra 20.00 for him to dispose of.
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Same here, and they won't scratch your fresh wheels. But they are an independent shop in an old Phillips 66 station that has been in the family for generations. Not corporate.
I am glad they are here.
 
I have been running radials on every vehicle I have owned since the early '70's except for my '36. I am getting ready to replace the tires on my '36 with radials, most likely from Coker.
Tire inflation on passenger cars is effected by two things. The vehicle manufacture is more concerned with ride, therefore the normal inflation on the old bias ply tires was 28-30 lbs. If the motorist read the owners manual that came with the vehicle he would note that the manual generally stated that the inflation should be increased 2 to 4 lbs to allow for added load and/or sustained highway speeds.
Tire manufactures are generally more concerned with tire performance and safety, therefore their recommendations are generally in the 32-34 range for radial tires.
The whole game changed with radial tires. Radial tires like higher tire pressures. My '97 Cherokee recommends P215/75R15 at 33 lb., I use P235/75R15 @ 35 lb. My front tires show no sign of shoulder scuffing or cupping within the tread. I generally rotate the tires every 5K.. My Cherokee has 153K on the odometer.
I have a 2012 GM Suburban that has 85K on it. I generally run 4 extra pounds in the tires, the unit is on its second set of tires. I have a large diesel RV, 125K on the odometer, that has 22.5, E rated radial tires front and rear. The vehicles recommended tire pressure is 95 front/rear. I run 105 front and 95 on the rear duals.
Several years ago there was a big safety issue with the Ford Expaditions that had Firestone radials. The tires were coming apart resulting in several deaths. There was a lot of media coverage about the tire issue, Ford blamed Firestone, Firestone claimed they had built the tires to Fords spec's. Ford got stuck with the liability claims because they had instructed Firestone with spec's that did not meet the DOT standard. Ford also sent out letters to customers instructing them to lower the pressure 2 lb's from the vehicles recommended pressure, which was lower than Firestone's recommended pressure.
 
All good advice Paul, and here in Western Oregon.. Molalla Tire Disposal charges $1 per tire
if you bring it in..All the tire store use Molalla Tire Disposal, so you can dicker the charge down. Independent tire stores are usually cheaper for services and if you leave the job for a slack time of day you get a better deal. Coker has free shipping to the Portland April swap, bad timing now. Newc RG #9
 
Yes, the original, slightly rusty rims on my 52 Merc held the tubless radial tires I installed just fine. Handles nice but I find them hard riding. For you guys that never run off paved roads it might not be an issue but I swear these steel belted radials feel every pebble on the gravel road and transmit it through the whole body. I don't remember the old bias ply tires of the 60s doing that but maybe I've just been spoiled by today's smoother riding vehicles . My old 81 GMC and 97 Blazer seem to absorb and eliminate all the road roughness unlike the Merc. And I'm only running 28 or less psi in the Mercs P235-70x15 tires too.
 
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