Truck Rear End Gear Ratio Explained

Count the number of teeth on the ring gear and the pinion. In the image below we have 50 teeth on the ring gear and 11 on the pinion so the formula looks like this.

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The standard axle ratio found in a GMC truck or SUV has been carefully selected according to the vehicles specific body style and engine in order to provide the best all-around mix of performance towing strength and efficiency.

. For a person who tows more often and heavier loads the 373 or 410 may be more appropriate. You divide the number of teeth on the ring gear by the number on the pinion. Knowing how to calculate the rear end gear ratio to choose the right one is not a must but.

1800 RPM 65693811 2731. If you constantly have a. But what does 2161 mean.

The ratio is simply the number of teeth on ring gear divided by the number of teeth on pinion. EXAMPLE With Overdrive 30. 2000 RPM 65693811 3041.

Low gears give fast acceleration high gears give better cruising. Especially with the 10 speed trans. Axle Ratio RPM X Tire Size Speed MPH X 336 Example 488.

Divide the number of the ring gears teeth by the number of the pinions teeth. Tall gear ratios have LOW drive shaft rotations and short gear ratios. Rear end gear ratio is boiled down to lower numerical values giving better acceleration torque top speeds and better fuel economy.

What are tall and short gear ratios. The gear ratio most interesting to 4x4 truck owners is the ratio between the driveshaft and axles - the differential gear ratio or axle gear ratio. 1941 2159 ratio.

First locate your current gear ratio and tire diameter and then find your approximate RPM at 65 MPH then reference your new tire diameter with your desired RPM to find the new gear ratio needed. Engine RPM Cruise Tire Revolutions Per Mile Rear-end Gear Ratio. There is a LOT of sciencetestingetc behind the best transmission gearingrear end gearing to get the best fuel economy.

Method 1 requires that you take apart your differential but there many be an easier way. The average speed today is 70 miles per hour. Much has changed over the past 5 years or so with axle ratios.

A smaller engine will need a lower rear end to give adequate acceleration. Give us a call at 800-216-1632 to get started. The first time you wade into the gears universe you will encounter several terms such as gear ratio rear end gear systems or trains etc.

Many big companies in the US like to use a 10 speed direct transmission 11 in 10th gear with a relatively high rear end ratio of 2641. We have a large selection of gear sets in stock and can recommend the correct. The most popular rear-end ratio in trucks today is the 355 which sort of averages towing power and fuel economy.

1 to 1 or direct gear is always the best gear for fuel mileage quietness cooler temperatures in the transmission and more pulling power. 340 3 392 3998 lbft 456 gear ratio. This will give you the axle ratio.

My company bought those trucks used pretty cheap and then put Rigmasters on. The rear ends are 355 gears. That said if you regularly tow heavy trailers.

A 373 offeres higher RPM which equals torque but an empty truck bed on a flat highway doesnt need such a low gear. So if you install a bigger more powerful engine you probably. It is controlled by the number of teeth on the ring vs.

Check out the image below. The higher the number the lower the ratio becomes. It depends on what you find.

A 13 is better for mpg but lots of the high ratio trucks have OD transmissions even in 9 and 10 speeds. Axle ratio is written as well a ratio such as 2161 in the case of Detroits fastest direct drive axle ratio offering. A high numerical gear ratio is called a low gear or low rear end and vice versa.

For instance the 3421 ratio included on many Canyon V-6 and Sierra 1500 models offers a good all-around blend. A 373 ratio is suitable for regular light towing. However to run in direct gear the rear gears must be either 264 247 221 and I think there is even a higher gear than the 221.

Poll closed Aug 12 2007. Engine rpm 1trans ratio 1rear axle ratio Tire rpm Engine torque trans ratio rear axle ratio Torque output at tires Therefore RPMS. What it all comes down to is speccing the truck.

FIGURING REAREND GEAR RATIO Ring Pinion FORMULA. General Motors rear end differentials are referred to by the diameter of the ring gear ie. For example a 216 ratio could have 41 teeth on the gear and 19 teeth on the pinion.

1800 RPM 65693811 2731 x 130 3541. Two common base axle ratios for trucks are 308 and 342. 340 3 355 3621 lbft 392 gear ratio RPMS.

The gear ratio of the set is 4541. But you should consider a 331. Rear End Gear Ratio Discussion in Ask An Owner Operator started by Gazoo Aug 5 2007.

A more powerful engine can use a higher rear end to give relaxed cruising and a higher top speed. What is gear ratios referring to. I recommend 3731or 4101 ratios for those who regularly tow heavy trailersand as I said above 410s for anyone going to larger tires.

3000 13 1355 282rpm at the tire 26 mph TORQUE. If you plan on towing a fifth-wheel trailer or anything heavier than 5000 pounds you should consider a 41 axle ratio. 75 inch 85 inch 105 inch.

The ring gear has 50 teeth and the pinion has 11. A ratio of 456 means that as the axle turns one whole circle the driveshaft turns 456 circles. Our experts will help you find the correct ring and pinion set for your particular application.

So when you buy your next new truck put a check mark next to the box that lists the optional axle ratio best suited for your driving needs and future upgrades. 3000 13 1392 255 rpm at the tire 23 mph TORQUE. The 315 wont be a problem.

This is a good ratio for the occasional towing or hauling individual. A 41 ratio allows a towing vehicle to start moving without as much throttle. A 290 gear ratio means the drive shaft turns 29 times in one full turn of the rear wheels.

Rear end gear ratios or final drive ratio refers to the number of revolutions the drive shaft turns compared to one full revolution of rear wheels.

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