Spare Tire Question

[Lance1985]

Thinking about new tires on my 2019 RAM 1500 and am happy with ride and performance on the original tires and plan to get identical replacements. I have never had a flat and assume the spare is identical with the original four tires. Since the spare is underneath the frame and never receives UV light or direct heat from the sun; is there any reason not to use it when replacing the tires, thus saving the cost of one tire?

 

[mikeru]

It's unlikely the spare is a match with the other tires. Depending on model and options it could be a full sized spare or a temporary spare. Even if it's full size it may have a different rim size. For example, on the 2020 Laramie with the ORG I used to own, it came with a full size spare. But while the rims on the truck were 20 inch, the spare had an 18 inch wheel. Our 2020 Limited has a temporary spare. I would not count on using the spare unless you look at it to verify what you have under there.

 

[crash68]

Not all truck get a spare that is identical to the rest, there is usually a temporary size.
Tires when properly cared for tires are good for 6-10 year although in Europe auto manufacturers don't recommend tires to be used after 6 years old.

 

[Tulecreeper]

OK, I'll ask. You've had this truck for 4 years and not once lowered the spare just to look at it or to see how it's done, or been under the truck to at least check the air occasionally?

However, to answer your original question: If the spare matches the original tires, then go ahead and use it to augment your new ones before it gets too old to use. But, you're still goiing to have to buy a new spare to replace it so how much have you actually saved?

 

[GTyankee]

You should drop your spare so that you know how to do it

Right now, chances are your spare has 17 pounds of air in it

getting the the jack out from under the passenger seat the first time is not fun, better to do it on a nice day, so if you have a need for it during the night in a rain storm, you will not have any surprises

 

[Dean2]

Without giving you all the other input, if it is the same make and size, use it as the number 4 new tire. Take the best take off tire and make that your spare. Saves you the cost of one new tire and since we almost never use the spare tire a used tire works fine.

My 1996 I used the spare twice when it was less than a year old because the factory tires blew out two sidewalls. After having all 4 replaced I never once used that spare in the next 24 years. Each time I bought 4 new tires for the truck, I would have them swap out the spare with the best of the takeoffs. That way your spare doesn't age out and crack.

 

[Tulecreeper]

Without giving you all the other input, if it is the same make and size, use it as the number 4 new tire. Take the best take off tire and make that your spare. Saves you the cost of one new tire and since we almost never use the spare tire a used tire works fine.

My 1996 I used the spare twice when it was less than a year old because the factory tires blew out two sidewalls. After having all 4 replaced I never once used that spare in the next 24 years. Each time I bought 4 new tires for the truck, I would have them swap out the spare with the best of the takeoffs. That way your spare doesn't age out and crack.

I forgot about using the best of the old for a spare. On the other hand, I did not follow my own advice. When I bought my last truck, a 2000 Silverado that I purchased new in Oct 1999, it came with a matching spare. When I sold it 2 months ago after 23+ years of driving, I had put 4 sets of tires on it but that original spare was still hanging under the back. I had pulled it out once about 15 years ago when I had a flat, drove on it for a day, then put it right back again. My bad...

 

[Farmer Fran]

Thinking about new tires on my 2019 RAM 1500 and am happy with ride and performance on the original tires and plan to get identical replacements. I have never had a flat and assume the spare is identical with the original four tires. Since the spare is underneath the frame and never receives UV light or direct heat from the sun; is there any reason not to use it when replacing the tires, thus saving the cost of one tire?

Sunlight or UV is only % of the problem. Temperature changes also play in a factor. I have a Wrangler with the rear mounted tire and do a 5 tire rotation. You will be safer in that situation in all aspects.

So looking at your question you should theoretically have more mileage, be safer and come out break even on cost if you replace all 5 on a 5 tire rotation. Safer is the key, because you look at the spare every 7500 miles, instead of an emergency.

 

[Badger 13]

I check tire pressure on the spare when I check the tires, which is quite often. It is easy since the valve stem faces down. I lower the spare at least once a year and lube up the cable and anything else that can be lubed. When it is down, I treat the tire with Aerospace 303 Protectant to help preserve it. I do not use the spare in my tire rotation since it is different brand tire than what I currently have on the truck.

 

[Lance1985]

Sunlight or UV is only % of the problem. Temperature changes also play in a factor. I have a Wrangler with the rear mounted tire and do a 5 tire rotation. You will be safer in that situation in all aspects.

I assume "rear mounted" means that it is exposed outside of the vehicle and therefore exposed to direct sunlight with damaging ultraviolet radiation. That is a different situation than one mounted under the frame.