RUN
THE
NUMBERS
Pre-build math – gear ratio, speed/RPM, tire-size impact, pinion angle. Run it here, then call us to spec the job.
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MATH WE DID SO YOU DON'T HAVE TO
Free calculators for re-gear planning, tire-size impact, speedo correction, and pinion-angle setup. Built in-browser, no sign-up.
GEAR RATIO CALCULATOR
SPEED & RPM
TIRE SIZE CHANGE
TRANSMISSION RATIO
FREE TOOLS
GEAR RATIO CALCULATOR
SPEED & RPM
TIRE SIZE CHANGE
TRANSMISSION RATIO
FREE TOOLS
01 · GEAR RATIO jawsgear.com
Gear Ratio Calculator
Ring & pinion gear ratio from tooth counts.
25
55
7
25
Gear Ratio
—
:1
Nearest Standard
—
:1
Jaws Recommends
03 · RPM jawsgear.com
RPM Calculator
Engine RPM at a given speed for automatic and manual, 1:1 and overdrive.
:1
2.5 :1
6 :1
mph
0 mph
100 mph
″
24 ″
44 ″
Auto · 1:1 Final Drive
—
rpm
Auto · .7 Overdrive (AOD)
—
rpm
Manual · 1:1 Final Drive
—
rpm
Manual · .7 Overdrive
—
rpm
Jaws Recommends
02 · TIRE SIZE jawsgear.com
Tire Size Calculator
Overall tire diameter from a metric size (e.g. 225 / 45 / 17).
mm
135 mm
355 mm
%
25 %
85 %
″
13 ″
24 ″
Tire Diameter
—
″
Sidewall Height
—
″
Diameter (mm)
—
mm
Jaws Recommends
04 · RPM BY TRANS jawsgear.com
RPM by Transmission Ratio
Engine RPM at speed for a specific transmission gear. Pick your transmission to fill the ratio, or enter it manually.
:1
2.5 :1
6 :1
mph
0 mph
100 mph
″
24 ″
44 ″
:1
0.5 :1
8 :1
Choose an option…
Engine RPM
—
rpm
Overall Ratio
—
:1
Jaws Recommends
why choose us
4.5/5.0
88+ Reviews on Google
Real Feedback. Real Results.
Andy Deck
Toyota Tacoma
Took my Tacoma in for a 5.29 regear and they knocked it out fast. Immediately noticed a difference and wish I'd done it sooner. Even on stock wheels and tires, the Tacoma benefits from a regear. Knowledgeable crew, no BS, just solid work. Highly recommend.
Carl Espy
99 Toyota Tacoma
Jeff and Omar were honest and upfront, with great options for my rusty assembly. They troubleshot their way to getting me back on the road. A bad differential isn't fun, but they took their service above and beyond — real knowledge and professionalism.
Justin Brown
This place is great. They stand by their work, have excellent customer service, and quick turn-around times. Would highly recommend them.
Alfredo Luna
Differential Rebuild
Went in for a basic rebuild, and after inspection there were more issues with the differential. Reasonable pricing and they still gave me 10% off labor. Differential feels way better — no more noises or clunking. Thank you!
Tiffany Weber
Quick to accept the truck, quick to fix it! Great price.
