275/50R23 vs 295/45R23
Going from one to the other changes the overall height by -1.1 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 275/50R23 | 295/45R23 | Change |
|---|---|---|---|
| Overall height | 33.8" | 33.5" | -1.1 % |
| Sidewall | 5.41" | 5.23" | -3.5 % |
| Section width | 275 mm | 295 mm | +7.3 % |
| Circumference | 106.3" | 105.1" | -1.1 % |
| Revs per mile | 596 | 603 | +1.1 % |
| Axle height | 16.91" | 16.73" | -4.8 mm |
| Approved rim width | 7.5–10" | 8.5–11" | overlap 8.5–10" |
Both are approved on a rim 8.5" to 10" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 275/50R23. Fit 295/45R23 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.7 mph | -0.3 |
| 50 mph | 49.4 mph | -0.6 |
| 70 mph | 69.2 mph | -0.8 |
| 90 mph | 89.0 mph | -1.0 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,889 on the road, so it over-counts by 111. At a true 70 mph the first turns 696 times a minute, the second 703.