OEM Safe
Within ±3%
Inside factory tolerance — ABS, ESP and cruise control stay calibrated.
Fitment comparison
245/40 R18versus235/35 R19
Δ Ø -6.1 mmSpeedo -0.93%OEM-safe
235/35 R19 is shorter than 245/40 R18 — quicker gearing feel, tighter arch gap, livelier throttle response.
Plus-sizing from 245/40 R18 to 235/35 R19 keeps overall diameter close to factory while opening room for a larger 19-inch wheel. This sizing approach barely shifts the rolling circumference. The shorter sidewall gives the tire a firmer, more responsive feel and sharpens steering input.
Dashboard speed shifts only marginally — within the noise of normal OEM tolerance. Diameter change stays inside the conservative ±3% safety window — an OEM-safe fitment on most vehicles.
TakeCommon upgrade for sportier handling and a tighter wheel-gap look on the same vehicle.
Quick fitment verdict
245/40 R18 → 235/35 R19 at a glance
Fender Clearance
Clears fender
Width and diameter stay close to stock — arch clearance unchanged.
Speedometer Impact
-0.93%
At a true 100 km/h the dash reads 99.1 km/h — negligible.
Daily Driving
Livable
Daily use is fine; expect a slightly different ride and cruise rev count.
Side-by-side telemetry
Dimensional read-out
Current
245/40 R18
- Diameter
- 653.2 mm
- Sidewall
- 98.0 mm
- Wheel
- 18″
- Width
- 245 mm
Δ delta
Ø -6.1 mm
SW -15.8 mm
RH -3.1 mm
NewNew
235/35 R19
- Diameter
- 647.1 mm
- Sidewall
- 82.3 mm
- Wheel
- 19″
- Width
- 235 mm
Real-world effects
How this swap actually feels
- Steering response89/100 · Sharper turn-in
- Ride comfort31/100 · Firmer ride
- Fuel economy56/100 · Slightly lower drag
- Highway cruising56/100 · Higher cruise revs
- Pothole resistance23/100 · Less wheel protection
Shareable card
Generate fitment card
Export a garage-grade telemetry card of this comparison — perfect for forums, Reddit and Discord.
Ride height
Lower stance
Chassis drops — tighter arch gap, more aggressive stance.
New tire drops ride height by ~3.1 mm — tighter arch gap, lower stance.
Suspension travel · arch clearance
Wheel gap
Wheel sits closer to the fender
How the arch-to-tire gap reads from across the parking lot — the visual stance change everyone notices first.
245/40 R18
235/35 R19
Wheel-gap Δ-3.1 mm
Static · unloaded chassis
Fender relationship
Tucked · Flush · Poke
The visual relationship between the tire's outer edge and the fender lip — the lens enthusiasts use to judge a fitment.
Tucked
Inside fender
Flush
Lip-aligned
Poke
Outside fender
Width & offset dependent
Speedometer reality
Dash reads 99.1 km/h
Shorter rubber: dashboard reads conservatively low — you're slower than it claims.
ABS · ESP · cruise control
Setup telemetry
How this setup changes the car
Driver-perspective read-out of the 245/40 R18 → 235/35 R19 swap — steering, comfort, stance and dash behavior in plain enthusiast language.
Steering feel
-15.8 mm sidewallSharper steering response
Shorter sidewall transmits inputs faster — quicker turn-in, more confident on-center feel.
Ride firmness
40% → 35%Slightly firmer over rough pavement
Expect more chatter on broken tarmac and a sharper pothole strike — keep an eye on wheel damage risk.
Fender relationship
-10 mm widthFender gap reads near-identical
Width delta is too small to change stance — same visual signature as OEM.
Speedometer behavior
-0.93%OEM-safe speedometer reading
Inside the factory ±3% tolerance — ABS, ESP and cruise control behave as designed.
Daily drivability
Ø -6.1 mmLivable upgrade with minor trade-offs
Daily use is fine; expect a slightly different cruise rev count and a touch more road feel.
Direct answer
Is 235/35 R19 OEM-safe?
Yes. Overall diameter changes by -0.93% versus 245/40 R18. OEM-safe. Speedometer, ABS, ESP and gearing remain inside the factory tolerance.
Direct answer
Will 235/35 R19 rub?
Unlikely. Width changes by -10 mm and diameter by -6.1 mm. Very unlikely to rub with OEM wheel offset.
Direct answer
Does the speedometer change?
Yes — by -0.93%. Swapping 245/40 R18 for 235/35 R19 changes overall diameter, so at an indicated 100 km/h your true speed becomes 99.1 km/h. That's within the ±3% OEM tolerance — no recalibration needed.
Direct answer
Does lower sidewall affect comfort?
Yes — firmer ride. Sidewall changes by -15.8 mm (40% → 35%). Ride becomes firmer and steering sharper, but potholes and expansion joints hit harder and wheel damage risk rises.
Current Tire
245/40R18
New Tire
235/35R19
Fitment · Scaled comparison
● Excellent fit
245/40 R18
Diameter
-6.1 mm
-0.93%
Sidewall
-15.8 mm
Speedometer
99.1 km/h
at true 100
Clearance
Excellent fit
235/35 R19
Ground line · Scaled comparison
Excellent Fit
Within ±3% — safe for daily driving
Diameter change
-6.1 mm
-0.93%
Speedometer at 100
99.1 km/h
-0.93% error
Ground clearance
-3.1 mm
ride height delta
Sidewall change
-15.8 mm
revs/km: 491.9
Permalink for this comparison:
/compare/245-40-r18-vs-235-35-r19Detailed comparison
| Metric | 245/40 R18 | 235/35 R19 | Difference |
|---|---|---|---|
| Overall diameter | 653.2 mm | 647.1 mm | -6.1 mm (-0.93%) |
| Sidewall height | 98.0 mm | 82.3 mm | -15.8 mm |
| Circumference | 2.052 m | 2.033 m | -19.2 mm |
| Revs / km | 487.3 | 491.9 | +4.6 |
| Ground clearance | reference | -3.1 mm | -3.1 mm |
| Speedometer @ 100 km/h | 100.0 km/h | 99.1 km/h | -0.93 km/h |
Verdict: excellent
Within ±3% — speedometer, ABS and traction control should behave normally.
Dimensional comparison
Side-by-sideScaled engineering side-profile of both tires. Width, sidewall and overall diameter are dimensioned so you can see the change at a glance — without parsing the numbers.
Current
245/40 R18- Profile
- 40%
- Circumference
- 2.052 m
New
235/35 R19- Profile
- 35%
- Circumference
- 2.033 m
Side-by-side fitment
GeometryCurrent
245/40 R18- Section width
- 245 mm
- Aspect ratio
- 40%
- Sidewall
- 98.0 mm
- Wheel diameter
- 18″(457 mm)
- Overall diameter
- 653.2 mm(25.72″)
- Circumference
- 2.052 m
- Revs / km
- 487.3
New
235/35 R19- Section width
- 235 mm
- Aspect ratio
- 35%
- Sidewall
- 82.3 mm
- Wheel diameter
- 19″(483 mm)
- Overall diameter
- 647.1 mm(25.48″)
- Circumference
- 2.033 m
- Revs / km
- 491.9
Real-world consequences
Pros / consNarrower tire (-10 mm)
Section width- Better aquaplaning resistance
- Lower rolling resistance and slightly better MPG
- Quieter ride, less tramlining
- Lighter unsprung mass on the corner
- Less dry grip at the limit
- Smaller contact patch under hard braking
- Stance can look tucked or undersized
Lower profile (-5% aspect)
Sidewall- Sharper turn-in and less sidewall roll
- More planted on smooth tarmac
- Bigger brake / caliper visual real estate
- Harsher ride over expansion joints and potholes
- Higher wheel-damage risk on impacts
- Less curb protection for the rim lip
- More sensitive to correct tire pressure
+1″ rim upsize
Wheel diameter- OEM+ look, fills the arch better
- Sharper response with matching low-profile rubber
- Bigger brake clearance for upgrades
- Heavier wheel, more unsprung mass
- Harsher ride, more wheel-damage risk
- Tire and wheel cost both go up
How it changes driving feel
Seat-of-the-pantsSteering response
Similar feel
Ride comfort
Comparable
Road noise
Similar cabin noise
Wet / aquaplaning
Comparable wet behavior
Fuel economy
Negligible change
Curb / pothole protection
Higher wheel-damage risk
Cluster preview
Within toleranceSpeedometer impact
At a true 100 km/h, your dashboard will read 99.1 km/h after switching to 235/35 R19 — a -0.93% offset. Use the speedometer error calculator for any indicated speed, and the speedometer error guide for the full background.
Ground clearance change
The new tire's half-diameter changes ride height by -3.1 mm. Small differences are absorbed by suspension travel, but anything beyond ±10 mm can affect headlight aim, fender clearance and bump-stop margin. See the plus-sizing guide before committing.
Back to
245/40 R18
Back to
235/35 R19
Drivers also compare
Closely-related fitments and plus-size swaps for 245/40 R18 and 235/35 R19.
215/45 R18 vs 245/40 R18
Wider variation on the same rim — more grip, less clearance.
Δ 0.38%
245/40 R18 vs 275/35 R18
Wider variation on the same rim — more grip, less clearance.
Δ 0.54%
225/45 R18 vs 245/40 R18
Wider variation on the same rim — more grip, less clearance.
Δ 0.99%
235/35 R19 vs 245/35 R19
Wider variation on the same rim — more grip, less clearance.
Δ 1.08%
225/35 R19 vs 235/35 R19
Wider variation on the same rim — more grip, less clearance.
Δ 1.09%
245/40 R18 vs 255/40 R18
Wider variation on the same rim — more grip, less clearance.
Δ 1.22%
235/40 R18 vs 245/40 R18
Wider variation on the same rim — more grip, less clearance.
Δ 1.24%
235/35 R19 vs 255/35 R19
Wider variation on the same rim — more grip, less clearance.
Δ 2.16%
Related topics
Comparison hub
Back to the tire size comparison calculator
Browse every wheel and tire fitment comparison, by rim size or popularity.