Eliminating spare tires

[Bird]

Like WilliamBos said, there's a very good reason for bigger brakes sometimes. I didn't really like the 19.5" wheels on our motorhome, but when you're running 18k pounds, plus towing another 2500 pounds. maybe the bigger brakes were worth it. And when we had a fifth-wheel travel trailer with two 3500 pound axles and 10" brakes, the brakes weren't bad, but I don't think you could have adjusted them to a point of being able to lock them up. But when I replaced everything from the frame down with 5200 pound axles and 12" brakes (wider brake shoes, too), I could very easily lock up the brakes.

 

[Ken45101]

Bigger wheels and tires give bettrr final drive ratios and help mpg ratings. They alsp add ground clrarance but do cost. You pay to play.

Smallest wheel I have in my fleet is 17"

Chris

If they want to change the final drive ratio, that's what the differential gearing is for.

Tires are relatively reliable today but problems still do happen. Try getting a replacement tire on a Sunday evening in the middle of a long distance trip! Don't forget, the space saver spares are usually rated for 50 miles distance and 50 mph max.

Car tires shouldn't be as bad but I've had to wait 6 weeks for the factory to produce new tires for the motorhome and it took a couple of days to get a replacement spare for the horse camper.

 

[JDgreen227]

As Ken 45101 says, differential gearing is a more practical way to change overall ratios than is by changing to a larger tire. The problem is, if you go to far in tire upsizing the engine may end up running at an rpm too low for the power curve. While people who maintain their tires properly rarely have a flat tire today, there are going to be situations where the "flat-fix kits" automakers provide as an alternative to a real spare are going to be useless as far as a repair goes. And good luck at getting the replacement tire you need when you need it. Two weeks ago I purchased a set of new Michelins for my wife's car, they were a common size and model, yet even Discount Tire had only 3 in stock and we had to wait for them to obtain a fourth tire. The odds of being able to get a replacement on a Sunday evening 500 miles from home are d*** poor.

 

[cmore]

As Ken 45101 says, differential gearing is a more practical way to change overall ratios than is by changing to a larger tire. The problem is, if you go to far in tire upsizing the engine may end up running at an rpm too low for the power curve. While people who maintain their tires properly rarely have a flat tire today, there are going to be situations where the "flat-fix kits" automakers provide as an alternative to a real spare are going to be useless as far as a repair goes. And good luck at getting the replacement tire you need when you need it. Two weeks ago I purchased a set of new Michelins for my wife's car, they were a common size and model, yet even Discount Tire had only 3 in stock and we had to wait for them to obtain a fourth tire. The odds of being able to get a replacement on a Sunday evening 500 miles from home are d*** poor.

I had a 98 Camaro and ran over a peace of metal that slit the tire. Luckily it had a compact spare and was able to get to a station. An fix a flat would have been useless.

I live in a rural area and don't even have cell service in some places.

Chev could have made the spare tire storage area large enough to put in a spare. The base model has a 17" and u can get up to a 22".

 

[Diamondpilot]

You can blame the current administration for high tire prices. Look into it. There is something like a 40% tax on import tires.

Chris

 

[Bird]

As Ken 45101 says, differential gearing is a more practical way to change overall ratios than is by changing to a larger tire. The problem is, if you go to far in tire upsizing the engine may end up running at an rpm too low for the power curve. While people who maintain their tires properly rarely have a flat tire today, there are going to be situations where the "flat-fix kits" automakers provide as an alternative to a real spare are going to be useless as far as a repair goes. And good luck at getting the replacement tire you need when you need it. Two weeks ago I purchased a set of new Michelins for my wife's car, they were a common size and model, yet even Discount Tire had only 3 in stock and we had to wait for them to obtain a fourth tire. The odds of being able to get a replacement on a Sunday evening 500 miles from home are d*** poor.

Yep, you're right, of course. Isn't part of the problem too many choices? If you were buying tires for a car 50 years ago, how many sizes were there, and how many manufacturers were there? There's so many now that I don't think any dealer could stock all of them. And 5 years ago when I bought the new set of of B. F. Goodrich Long Trail T/A tires for my Ford Ranger, neither Discount Tire, NTB, Sears, nor the local Ford Dealer had any in stock for 15" wheels, as the Ranger has, although they did have them for the 16" wheels. Of course Discount Tire ordered them for me, but if I'd been in a big hurry, I'd have sure been out of luck.

 

[JDgreen227]

You can blame the current administration for high tire prices. Look into it. There is something like a 40% tax on import tires.

Chris

The Michelins I recently purchased were made in Canada...not sure if that qualifies as an import or not. Discount Tire had something like 30+ different models in the size I needed, the prices ranged from about $114 to $155....not sure how many, if any, were made in the USA.

 

[dodge man]

Picture a large pick up truck running on tires and rims that are designed for a Prius. How would it handle and how would it stop? Not very good would it. There is a reason they have gone to bigger tires and rims, they help a vehicle stop better and handle better. Yes, there is a cost, mainly in weight.

 

[JDgreen227]

Picture a large pick up truck running on tires and rims that are designed for a Prius. How would it handle and how would it stop? Not very good would it. There is a reason they have gone to bigger tires and rims, they help a vehicle stop better and handle better. Yes, there is a cost, mainly in weight.

I own a Y2K GMC Yukon XL that came with 16 inch Load Range E tires standard...even when towing 6500 pounds with a hitch weight of nearly 900 pounds, I never felt it needed larger tires nor brakes.

OP said removing the spare tires for weight savings is really stupid when they add so much extra weight with huge tires and wheels. That is what I was trying to say. As for handling being better, I would say the extra mass of unsprung weight cancels out the advantage of the larger tire. And what about the additional rolling resistance and it's effect on fuel usage?

 

[Diamondpilot]

Picture a large pick up truck running on tires and rims that are designed for a Prius. How would it handle and how would it stop? Not very good would it. There is a reason they have gone to bigger tires and rims, they help a vehicle stop better and handle better. Yes, there is a cost, mainly in weight.

You are right. My F350 SRW diesel 4x4 has the high 11,500# gvwr package. No way a small tire and wheel combo is going to do that. There is a reason it has 18" wheels.

Chris