Great article on gear ratios

[Cowpie]

Of course, you are entitled to your opinion on this. But it would be helpful if you could give something to substantiate your contention better than quotes from dead guys.

[i82much]

Of course, you are entitled to your opinion on this. But it would be helpful if you could give something to substantiate your contention better than quotes from dead guys.

Just go look at the different sprockets on an old 10 speed bike sometime.

[Cowpie]

You like to dig at me about comparing heavy trucks to pickups, yet you will compare pickups to bicycles?

[i82much]

https://en.m.wikipedia.org/wiki/Mechanical_advantage

[dasimmon]

Awesome article!! Thank you for posting! Extremely useful for me currently as i'm looking for a new truck. I personally had no idea that increasing tire size lowers the gear ratio...so glad I found this forum!!

[2017HD]

It was years ago now, but I went through a rear end gear ratio change - from a 3.08 to a 3.73 in an S-10 pickup. We had to determine exactly what component needed to be changed. We ended up with needing just a new ring and pinion set up and not a new housing. GM makes various sized housings, ring, and pinions as well as spiders. Depending on which ratio gear set you can change one or the other or maybe even all four components - at that point I would probably go to a junk yard and buy a used whole axle.

 

From this I believe that they are able to use the same ring gear with different pinions for at least 2 or 3 ratios. The same with the housing and spiders.

 

How strong all of these components are is well beyond most of our pay grades here. So we must trust that the engineers at GM have made them strong enough to handle the intended loads - and then some.

 

Back in the 80's GM put out trailering charts that suggested that you pair the largest engine and smallest rear end (numerically) to reach your desired CGWR. They figured that most of the time you would not be fully loaded and the engine would be loafing along, but when it came time for a load, the engine would be more than capable of handling it. Probably the reason we have a 3.73 paired with the DMax and 4.10 with the Gasser