The manual for my 2016 V60 says this for tires that can be used: 235/40/18 or 235/45/18

U

urdrwho

Joined
Nov 25, 2012
Messages
140
Location
PA, USA
The manual for my 2016 V60 says this for tires that can be used:

235/40/18 or 235/45/18

When I bought the car it had 235/40/18 on them and that's darn low profile for me and my wife's pain from chemo felt every bump. Recently went to 235/45/18 as per manual allowance. That extra bit of air, a cushion between me and the road helps (a bit). I don't care about flying around corners, I am in my 70's and those days are gone and a higher sidewall is ok with me. What about a half inch?

The problem is that the with a bigger aspect ration, my speedometer will be off a bit. Not much because I didn't change that much height.

Called Volvo to see about getting a computer update to calibrate the speedo. I was told the only thing they have is a software update if you change the wheels to a different size. Ok guys, that means you have software that calibrates for a different wheel/rim which means different diameter. Changing the aspect ratio does the same thing --- changes diameter. Service department said, yes I understand you but we only have software that can do this for a wheel/rim change. But a bigger or smaller rim will change the diameter and that what I did with the tire. Albeit not much of a change but a change.

I really don't want to get a speeding ticket for the difference of maybe 1.5 > 2 MPH difference in speed. Any ideas. Volvo has their VIDA system and that system doesn't play or share well with other shops.
 
urdrwho said:
The manual for my 2016 V60 says this for tires that can be used:

235/40/18 or 235/45/18

When I bought the car it had 235/40/18 on them and that's darn low profile for me and my wife's pain from chemo felt every bump. Recently went to 235/45/18 as per manual allowance. That extra bit of air, a cushion between me and the road helps (a bit). I don't care about flying around corners, I am in my 70's and those days are gone and a higher sidewall is ok with me. What about a half inch?

The problem is that the with a bigger aspect ration, my speedometer will be off a bit. Not much because I didn't change that much height.

Called Volvo to see about getting a computer update to calibrate the speedo. I was told the only thing they have is a software update if you change the wheels to a different size. Ok guys, that means you have software that calibrates for a different wheel/rim which means different diameter. Changing the aspect ratio does the same thing --- changes diameter. Service department said, yes I understand you but we only have software that can do this for a wheel/rim change. But a bigger or smaller rim will change the diameter and that what I did with the tire. Albeit not much of a change but a change.

I really don't want to get a speeding ticket for the difference of maybe 1.5 > 2 MPH difference in speed. Any ideas. Volvo has their VIDA system and that system doesn't play or share well with other shops.
Click to expand...

Don't know about Volvo. I can tell you that GM's position is that they will change the computer to a factory tire size-and they will do it only ONE TIME. The easy answer to to use a (GPS) program in your smartphone-but the difference is so small on your speedometer I don't think it's worth worrying about-especially if you have to pay a minimum amount of 1 hour of labor-probably at least two hundred dollars. I don't know anybody who got a ticket for going over 2 mph on a city street-or Interstate-UNLESS IT'S a school zone. They can be fussy about those.
 
According to tiresize.com the large tire will be 3.5% more circumference and when the speedo says 70MPH you will be doing 72.5mph - that is with the giant assumption that the speedometer was dead accurate at all points to begin with, which it likely was not.

Having said that I don’t think going from a 40 series to 45 series is going to solve your issue. I have 55 series on our RAV4 and it feels like my feelings are gonna fall out anytime I hit a pothole. Can you go to a smaller wheel - will it clear the brakes?
 
CKN said:
Don't know about Volvo. I can tell you that GM's position is that they will change the computer to a factory tire size-and they will do it only ONE TIME. The easy answer to to use a (GPS) program in your smartphone-but the difference is so small on your speedometer I don't think it's worth worrying about-especially if you have to pay a minimum amount of 1 hour of labor-probably at least two hundred dollars. I don't know anybody who got a ticket for going over 2 mph on a city street-or Interstate-UNLESS IT'S a school zone. They can be fussy about those.
Click to expand...
There is a freeway near Baltimore Maryland that has speed cameras. I'm not from Maryland, we go down there to go to Johns Hopkins. The speed limit is 55 but all those Maryland Baltimore commuters don't obey anything near that limit. I got a camera ticket, a warning. They allow you to go by the camera doing 61 mph and anything above it you can a photo ticket. No points given on your license but a $45 fine. Everyone knows where the camera are, except me, I don't know all of them. I try to keep it at 61 or below but sometimes if I need to be in a certain lane for an exit that is on the far left, I need to match the traffic or even faster.

So if I am doing 61 on the speedo in reality I am doing 63.22 and the camera would snap me a ticket. I'll have to try and remember.

Ah gone are the days you could take your car to a speedo shop, they could change out the gear, cable or whatever they could do for you. Nope, we are now at the mercy of the computer.

On our road the speed is 25 mph. They will allow you to hit 31 but above that they will ticket you. In the age of computers we are all watched and monitored down to the minuscule.

There are a lot of people who probably don't know their speed would change and use the manual that came with the car to change to a different tire size. Not knowing that they are changing the speedo calibration. Maybe the manual that came with the car shouldn't have options. ;)
 
urdrwho said:
There is a freeway near Baltimore Maryland that has speed cameras. I'm not from Maryland, we go down there to go to Johns Hopkins. The speed limit is 55 but all those Maryland Baltimore commuters don't obey anything near that limit. I got a camera ticket, a warning. They allow you to go by the camera doing 61 mph and anything above it you can a photo ticket. No points given on your license but a $45 fine. Everyone knows where the camera are, except me, I don't know all of them. I try to keep it at 61 or below but sometimes if I need to be in a certain lane for an exit that is on the far left, I need to match the traffic or even faster.

So if I am doing 61 on the speedo in reality I am doing 63.22 and the camera would snap me a ticket. I'll have to try and remember.

Ah gone are the days you could take your car to a speedo shop, they could change out the gear, cable or whatever they could do for you. Nope, we are now at the mercy of the computer.

On our road the speed is 25 mph. They will allow you to hit 31 but above that they will ticket you. In the age of computers we are all watched and monitored down to the minuscule.

There are a lot of people who probably don't know their speed would change and use the manual that came with the car to change to a different tire size. Not knowing that they are changing the speedo calibration. Maybe the manual that came with the car shouldn't have options. ;)
Click to expand...

A cellphone App is another option.
 
SC Maintenance said:
According to tiresize.com the large tire will be 3.5% more circumference and when the speedo says 70MPH you will be doing 72.5mph - that is with the giant assumption that the speedometer was dead accurate at all points to begin with, which it likely was not.

Having said that I don’t think going from a 40 series to 45 series is going to solve your issue. I have 55 series on our RAV4 and it feels like my feelings are gonna fall out anytime I hit a pothole. Can you go to a smaller wheel - will it clear the brakes?
Click to expand...
No we can't go smaller, it won't clear the brakes. Maybe it is because they are new or the tire type but there is a difference. They are wild looking tires. Michelin Cross Climate 2 and they get very good reviews for comfort.

If it doesn't work out, to help keep the car, the price was not astronomical for the tires. About $1,050 installed, balanced, tax and out the door. New wheels and tires cost a lot more just for an experiment.

I know about the motor problems but we had been looking at the Lincoln MKC series. We had driven some and Lincoln still has that senior citizen ride that 55 years ago, as a young driver, I would have passed on. I figured $1000 was worth a try over spending the money in the inflated used car market.
 
urdrwho said:
The manual for my 2016 V60 says this for tires that can be used:

235/40/18 or 235/45/18

When I bought the car it had 235/40/18 on them and that's darn low profile for me and my wife's pain from chemo felt every bump. Recently went to 235/45/18 as per manual allowance. That extra bit of air, a cushion between me and the road helps (a bit). I don't care about flying around corners, I am in my 70's and those days are gone and a higher sidewall is ok with me. What about a half inch?

The problem is that the with a bigger aspect ration, my speedometer will be off a bit. Not much because I didn't change that much height.

Called Volvo to see about getting a computer update to calibrate the speedo. I was told the only thing they have is a software update if you change the wheels to a different size. Ok guys, that means you have software that calibrates for a different wheel/rim which means different diameter. Changing the aspect ratio does the same thing --- changes diameter. Service department said, yes I understand you but we only have software that can do this for a wheel/rim change. But a bigger or smaller rim will change the diameter and that what I did with the tire. Albeit not much of a change but a change.

I really don't want to get a speeding ticket for the difference of maybe 1.5 > 2 MPH difference in speed. Any ideas. Volvo has their VIDA system and that system doesn't play or share well with other shops.
Click to expand...
I would verify that you actually have a problem first. More likely, your speedo was reading a bit fast, and now it will be accurate or a touch slow.
 
Seems as though Volvo considers the speedo discrepancy between the 40 and 45 series to be within a tolerance that they don't care about. Maybe it's calibrated (programmatically) for 42.5 profile to begin with so you're already "off" by 1.25 mph (based on going from 40 to 45 and that being 2.5 mph off).

urdrwho said:
My son says that Google Maps has a GPS that will show the speed.
Click to expand...
On Android phones it does, but not on iPhones. WAZE has a speedometer built-in on iPhone though. Don't know what you use though.... Either way, there are dozens of GPS-based speedometer apps available.
 
RooflessVW said:
I would verify that you actually have a problem first. More likely, your speedo was reading a bit fast, and now it will be accurate or a touch slow.
Click to expand...
I hadn't considered it, that's right. From what I've read the manufactures set the speedo to be higher than true speed so that you don't get a ticket and blame them, etc.
 
Hall said:
Seems as though Volvo considers the speedo discrepancy between the 40 and 45 series to be within a tolerance that they don't care about. Maybe it's calibrated (programmatically) for 42.5 profile to begin with so you're already "off" by 1.25 mph (based on going from 40 to 45 and that being 2.5 mph off).


On Android phones it does, but not on iPhones. WAZE has a speedometer built-in on iPhone though. Don't know what you use though.... Either way, there are dozens of GPS-based speedometer apps available.
Click to expand...
Think I'll check out the issue with the GPS app.
 
Why not just drive 3 mph under the indicated speed? If you want to go 60 mph, set the cruise, or your right foot at 57 mph on the speedometer. Or get at navigation unit. My Gamin Nuvi shows your actual speed in the corner of the screen.
 
Set cruise control to 59, drove with Google Maps and Google said 62 MPH. That's about the add on for the larger wheel. Darn I had hoped the speedo was off to begin with and now it would be accurate.
 
atikovi said:
Why not just drive 3 mph under the indicated speed? If you want to go 60 mph, set the cruise, or your right foot at 57 mph on the speedometer. Or get at navigation unit. My Gamin Nuvi shows your actual speed in the corner of the screen.
Click to expand...
That works as long as I remember and nobody else borrows the car. My problem is that I know and I like things to work as intended. So I'll have to find a way to forget it isn't working as intended.
 
Last edited:
atikovi said:
Speed cameras around here have a 12 mph grace period. Not sure if it's a county thing or statewide
Click to expand...
The problem I have with those **** camera's is you can be doing the exact speed limit but other's are not. There is a place in Baltimore what the exit isn't on the right side but the left side which means you have to get over into that lane where the fastest travel. To do so you can easily go over the limit but only for an instant. In that instant the camera snaps and you are had. It is not that you were habitually speeding, you had to make your way through the rats nest to get the lane you needed. If that makes sense. I just can't believe the software doesn't have the ability to subtract 2 MPH from the speedo or the techs just don't want to do it????
 
You must log in or register to reply here.

Similar threads

G
OE tire & wheel specs for 1977 Dodge D100 pickup?
Replies
4
Views
197
hemitom
U
  • Locked
I don't know - it seems more difficult to buy a car
2
Replies
37
Views
2K
dnewton3
U
I don't think I'll find or buy a used car
2 3
Replies
53
Views
4K
addyguy
S
Volvo iShift Transmission Oil - The Saga
Replies
4
Views
2K
4WD
M
1 Week Review - 2025 Toyota Tacoma Hybrid Limited
3 4 5
Replies
84
Views
20K
mikeduf
Back
Top Bottom