Trying to understand crawler gear ratios

[sumguy75]

What is the purpose of running different front and rear gear ratios? Is it for better turning radius? Other pros/cons? I'm just now really getting into crawlers a little more and have only run stock gear ratios so far.

 

[tntpoof]

turning radius..now what affects turning radius? not gear ratio..

 

[sumguy75]

Ok then what?

 

[coldvod]

I'll try to explain then i'll link a video or article that explains it better.

Basically your gear ratio is how many turns your input has to make for your output to make 1 360° turn.
The more turns your input makes, the more torque. The less turns the higher top speed* Cars use gear ratios in the transmission, diff, and transfer case if they have one.

*not sure go read/watch the links i have provided

Thats my short version of it. I'll go find a few sources to help you better understand. I'll update in an hour or so as I'm busy

 

[tntpoof]

Hyper links?

 

[coldvod]

here's how to calculate your gear ratios : https://www.theengineerspost.com/gear-ratio/
a simple video explaining what a gear ratio does in a car :

this page has useful info too : https://interestingengineering.com/science/machine-design-101-gear-ratios

 

[Doom!]

The difference is overdrive gearing in the front provides more pull from the front, providing more traction as the weight of the vehicle is displaced rearward by the climbing angle that would otherwise cause the rear wheels to dig in and spin, while trying to push the vehicle.

I hope that made sense, I'm not the greatest at explaining.

It does affect steering, by acting like a front wheel drive which can steer tighter than a rear wheel drive.

It would not be desirable in a faster vehicle because it would cause the rear to slide out kind of like braking.

What is the purpose of running different front and rear gear ratios? Is it for better turning radius? Other pros/cons? I'm just now really getting into crawlers a little more and have only run stock gear ratios so far.

 

[sumguy75]

The difference is overdrive gearing in the front provides more pull from the front, providing more traction as the weight of the vehicle is displaced rearward by the climbing angle that would otherwise cause the rear wheels to dig in and spin, while trying to push the vehicle.

I hope that made sense, I'm not the greatest at explaining.

It does affect steering, by acting like a front wheel drive which can steer tighter than a rear wheel drive.

It would not be desirable in a faster vehicle because it would cause the rear to slide out kind of like braking.

Ok that makes sense. So would front overdrive gearing be more for crawling only or is it also useful for a trail rig that does some moderate climbing?

 

[Chubaka]

Ok that makes sense. So would front overdrive gearing be more for crawling only or is it also useful for a trail rig that does some moderate climbing?

I've only heard of it for crawling. From what I heard is it allows the front some wheel speed to pull up on a trail truck I'd run factory, or overdrive all around for more wheel speed. My 10.2 I ran overdrive in the rear so I can do donuts.

 

[Doom!]

Overdrive is still good for trail trucks as long as your not hauling ass down the trails. If you drive it scale, it still has the benefit of getting over obstacles and inclines easier. When most people say crawler they really mean trail truck. I like the little extra pull myself. I think it depends on driving style and personal preference.

I've only heard of it for crawling. From what I heard is it allows the front some wheel speed to pull up on a trail truck I'd run factory, or overdrive all around for more wheel speed. My 10.2 I ran overdrive in the rear so I can do donuts.

 

[tntpoof]

it can be used in other applications. I've used that in clod racing for 15 years...