Rear axle ratios and impact on towing
Suppose you have a choice between two axle ratios, say they are a 3.09 and a 3.45. And let's say the vehicle has an 8 speed transmission, so there's plenty of gear flexibility. Ok, so there's roughl...
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Hi,
Either rear axle ratio will work fine. The truck will pick the highest gear that it can be in for a given load. So if you need 2,500 RPM to continue at a given road speed, then the truck will pick one of the 8 gear ratios and go with it.
With the 3.0:1 ratio, the truck can have a slightly lower engine speed, until it downshifts and can actually be turning faster than the 3.45 will have in the next higher gear on transmission.
So either one will make 200 HP at 3,000 RPM at say 45 MPH while going up a hill. If you need more power, either one will shift down one gear and bring up the engine RPM and increase the available HP as much as needed.
Fred.
Either rear axle ratio will work fine. The truck will pick the highest gear that it can be in for a given load. So if you need 2,500 RPM to continue at a given road speed, then the truck will pick one of the 8 gear ratios and go with it.
With the 3.0:1 ratio, the truck can have a slightly lower engine speed, until it downshifts and can actually be turning faster than the 3.45 will have in the next higher gear on transmission.
So either one will make 200 HP at 3,000 RPM at say 45 MPH while going up a hill. If you need more power, either one will shift down one gear and bring up the engine RPM and increase the available HP as much as needed.
Fred.
