Tire pressure and plus sizing?
- Thread starter Mikey V.
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Car spec 2 lbs??
whats the max psi listed on the side wall of your new tires?
IMO any thing over 30psi on that tire will make the ride rock hard. Will they fit without a clearance problem? You have not stated what car you are using them on, but it would seem that the car weight is about 3300-3400Lbs.I would say that 30psi would be a good starting point.FWIW---Oldtommy
Summer 32psi, winter 30psi. Check wear pattern and adjust accordingly.
35 PSIG all year. TPMS will go into alarm at 32 PSIG, something you want to avoid to protect your sanity.
Low profile tires such as your 45 Series commonly identify higher pressures on their side walls (40PSIG or more), to protect the expensive rims from potholes
Low profile tires such as your 45 Series commonly identify higher pressures on their side walls (40PSIG or more), to protect the expensive rims from potholes
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The first question to determine the tire pressure is what the load index of the old and new tyre. If it is same, you can use same pressure, if the new one is higher, you may have some flexibility to reduce pressure a bit.
However, most new tires, typically runs best with at least 29-30 psi.
However, most new tires, typically runs best with at least 29-30 psi.
I would try 36-38 PSI for a week then reduce 1 PSI every week until you find a good compromise between ride and handling.
My guess is around 32-34 PSI will be the best compromise of ride/handling, tread life and fuel economy.
My guess is around 32-34 PSI will be the best compromise of ride/handling, tread life and fuel economy.
Originally Posted By: mv6845
195/60/15 87H is original.
First off, a 205/45R17 is the correct plus size for this car.
But for what you have, if the oe psi is 29, you want 32 cold on these tires.
People's ideas of what proper tire pressure should be are pretty funny. There are load tables for every tire size & load rating, and the vehicle manufactures spec tire pressure for a reason, but everyone likes to make up their own rules.
195/60/15 87H is original.
First off, a 205/45R17 is the correct plus size for this car.
But for what you have, if the oe psi is 29, you want 32 cold on these tires.
People's ideas of what proper tire pressure should be are pretty funny. There are load tables for every tire size & load rating, and the vehicle manufactures spec tire pressure for a reason, but everyone likes to make up their own rules.
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Originally Posted By: mv6845
Thanks for the info. Was going to run 32 f&r
32 is the correct pressure as the minimum, sometimes different tire construction have different interaction with the suspension (soft/hard), so you can still adjust 1-2 psi to match the load, suspension and the road characteristics.
BTW XL rated need higher pressure compared to standard to support the same load, so happy experimenting !
Thanks for the info. Was going to run 32 f&r
32 is the correct pressure as the minimum, sometimes different tire construction have different interaction with the suspension (soft/hard), so you can still adjust 1-2 psi to match the load, suspension and the road characteristics.
BTW XL rated need higher pressure compared to standard to support the same load, so happy experimenting !
Originally Posted By: Johnny248
Originally Posted By: mv6845
195/60/15 87H is original.
First off, a 205/45R17 is the correct plus size for this car.
But for what you have, if the oe psi is 29, you want 32 cold on these tires.
People's ideas of what proper tire pressure should be are pretty funny. There are load tables for every tire size & load rating, and the vehicle manufactures spec tire pressure for a reason, but everyone likes to make up their own rules.
^^X 2
Allow me to explain further.
Tires can vary widely on how they feel at the same inflation pressure and load. What is being felt is the intentional design in the tire. It's supposed to feel that way, but many folks will draw the mistaken conclusion that different inflation pressures are needed.
Complicate this by changing tire sizes and the result is a whole range of opinion based on a mistaken premise.
Originally Posted By: mv6845
195/60/15 87H is original.
First off, a 205/45R17 is the correct plus size for this car.
But for what you have, if the oe psi is 29, you want 32 cold on these tires.
People's ideas of what proper tire pressure should be are pretty funny. There are load tables for every tire size & load rating, and the vehicle manufactures spec tire pressure for a reason, but everyone likes to make up their own rules.
^^X 2
Allow me to explain further.
Tires can vary widely on how they feel at the same inflation pressure and load. What is being felt is the intentional design in the tire. It's supposed to feel that way, but many folks will draw the mistaken conclusion that different inflation pressures are needed.
Complicate this by changing tire sizes and the result is a whole range of opinion based on a mistaken premise.
Originally Posted By: CapriRacer
Originally Posted By: Johnny248
Originally Posted By: mv6845
195/60/15 87H is original.
First off, a 205/45R17 is the correct plus size for this car.
But for what you have, if the oe psi is 29, you want 32 cold on these tires.
People's ideas of what proper tire pressure should be are pretty funny. There are load tables for every tire size & load rating, and the vehicle manufactures spec tire pressure for a reason, but everyone likes to make up their own rules.
^^X 2
Allow me to explain further.
Tires can vary widely on how they feel at the same inflation pressure and load. What is being felt is the intentional design in the tire. It's supposed to feel that way, but many folks will draw the mistaken conclusion that different inflation pressures are needed.
Complicate this by changing tire sizes and the result is a whole range of opinion based on a mistaken premise.
Perfect! x2
Originally Posted By: Johnny248
Originally Posted By: mv6845
195/60/15 87H is original.
First off, a 205/45R17 is the correct plus size for this car.
But for what you have, if the oe psi is 29, you want 32 cold on these tires.
People's ideas of what proper tire pressure should be are pretty funny. There are load tables for every tire size & load rating, and the vehicle manufactures spec tire pressure for a reason, but everyone likes to make up their own rules.
^^X 2
Allow me to explain further.
Tires can vary widely on how they feel at the same inflation pressure and load. What is being felt is the intentional design in the tire. It's supposed to feel that way, but many folks will draw the mistaken conclusion that different inflation pressures are needed.
Complicate this by changing tire sizes and the result is a whole range of opinion based on a mistaken premise.
Perfect! x2
I couldn't find a thread that really address is my topic so I'll ask here. Does anyone make a 235 / 70 R 17 10 ply tire for a Ford F 150? Or is my only option to go to a 245 7017 load range E? the truck is spec is 38 psi. what would be a good air pressure to runin a 245 70 17 10 ply on this truck?
Originally Posted By: FordFocus
I couldn't find a thread that really address is my topic so I'll ask here. Does anyone make a 235 / 70 R 17 10 ply tire for a Ford F 150? Or is my only option to go to a 245 7017 load range E? the truck is spec is 38 psi. what would be a good air pressure to runin a 245 70 17 10 ply on this truck?
First, you need to tell us what the vehicle tire placard says for tire size and inflation pressure. F-150's have been produced for decades and there are tons of versions with differing tire sizes and pressures.
Second, you need to be aware that tires frequently have letters in front of or behind the tire size - and they are important. For example, the tire sizes you are talking about are all LT metric tires and they have the letters "LT" in front of the tire size. They are different than P metric tires - with a "P" in front of the tire size. So when you talk about a tire size, be sure to include the letters.
LT235/70R17? If Tire Rack doesn't have, it very likely doesn't exist.
I see that there are F-150's that came with P235/70R17's inflated to 38 psi - and assuming that is what your vehicle tire placard says, then to carry the same load a P235/70R17 does at 38 psi, an LT245/70R17 needs 44 psi.
- and hopefully you will see why I am not a fan of using LT tires in place of P metric tires.
I couldn't find a thread that really address is my topic so I'll ask here. Does anyone make a 235 / 70 R 17 10 ply tire for a Ford F 150? Or is my only option to go to a 245 7017 load range E? the truck is spec is 38 psi. what would be a good air pressure to runin a 245 70 17 10 ply on this truck?
First, you need to tell us what the vehicle tire placard says for tire size and inflation pressure. F-150's have been produced for decades and there are tons of versions with differing tire sizes and pressures.
Second, you need to be aware that tires frequently have letters in front of or behind the tire size - and they are important. For example, the tire sizes you are talking about are all LT metric tires and they have the letters "LT" in front of the tire size. They are different than P metric tires - with a "P" in front of the tire size. So when you talk about a tire size, be sure to include the letters.
LT235/70R17? If Tire Rack doesn't have, it very likely doesn't exist.
I see that there are F-150's that came with P235/70R17's inflated to 38 psi - and assuming that is what your vehicle tire placard says, then to carry the same load a P235/70R17 does at 38 psi, an LT245/70R17 needs 44 psi.
- and hopefully you will see why I am not a fan of using LT tires in place of P metric tires.
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