Choice of rear axle ratio would you pick?

Badass69 · August 26, 2013

Ok, let me put this into perspective for you. For some people, their truck is their car, that has 4wd for the winter, and can haul a few things in the bed if needed. The 4.3 would have been plenty for me and most half ton truck buyers (I was actually considering it). Not everybody uses their truck for work, and loads it up to the max of it's capabilities. Sometimes I just have to load up the ATV, or get a load of mulch for around the house. Why do you think they've nearly turned into luxury vehicles, with heated and cooled seats and big fancy touch screens? What do you think of V6 half tons like the 3.6 Ram or the 4.3 Silverado? Are they complete garbage too, or do you think they serve a purpose? Sounds like you need a 3/4 ton if you're working your little 5.3's so hard.

Honestly learn how to read or do better at skimming. My trucks are 3/4 tons... and all run 6 liters. A 1500hd has a 6 liter... and a 4l80e and 8 lug axles lol. I don't work all of mine either... but having a truck that's actually legally useful is kinda nice.... and then I have a car which quite frankly is terrible on fuel anyway. Everything serves a purpose down to the 6 cylinder trucks.... like fleet parts haulers. That never was up for debate here...

Chris · August 26, 2013

Guys this pissing match has gone on long enough. All of you have opinions and its time to just let it go. This was a decent thread until the pissing match. I dont want to lock it or hide posts.

So please just let it go

Sent from my Samsung Galaxy S4 using Tapatalk 4

2017HD · August 26, 2013

In addition to the rear axle ratio you also need to look at the wheel and tire sizes too. The are the last factor in how much force in lbs is applied to the road. For you engineering types the formula for converting the rotational torque in lb-ft at the hub is to divide that number by the radius of the wheel and tire.

As far as using the "get up a go" test - I don't see where it is all that valid of determining how good or bad the drivetrain is. The ECM and TCM computers determine way more of how to handle the "I want to go faster" input and from what I have read, that is where GM is putting most of it's engineering efforts combining AFM, the throttle body, and transmission settings. We must also remember that the accelerator pedal is now connected to a sensor and not to any throttle linkage.

I feel that a better test is to see how the truck handles a load or a trailer.

In addition to the rear axle ratio you also need to look at the wheel and tire sizes too. The are the last factor in how much force in lbs is applied to the road. For you engineering types the formula for converting the rotational torque in lb-ft at the hub is to divide that number by the radius of the wheel and tire.

As far as using the "get up a go" test - I don't see where it is all that valid of determining how good or bad the drivetrain is. The ECM and TCM computers determine way more of how to handle the "I want to go faster" input and from what I have read, that is where GM is putting most of it's engineering efforts combining AFM, the throttle body, and transmission settings. We must also remember that the accelerator pedal is now connected to a sensor and not to any throttle linkage.

I feel that a better test is to see how the truck handles a load or a trailer.

GMC-AT · August 26, 2013

You want to start a good pissing match lets talk about the best brand of motor oil

For real.. 3.42 or 3.08 .. it's all preference depending on how you use the truck... little pro's and con's...

Joe_K · August 26, 2013

In addition to the rear axle ratio you also need to look at the wheel and tire sizes too. The are the last factor in how much force in lbs is applied to the road. For you engineering types the formula for converting the rotational torque in lb-ft at the hub is to divide that number by the radius of the wheel and tire.

As far as using the "get up a go" test - I don't see where it is all that valid of determining how good or bad the drivetrain is. The ECM and TCM computers determine way more of how to handle the "I want to go faster" input and from what I have read, that is where GM is putting most of it's engineering efforts combining AFM, the throttle body, and transmission settings. We must also remember that the accelerator pedal is now connected to a sensor and not to any throttle linkage.

I feel that a better test is to see how the truck handles a load or a trailer.

In addition to the rear axle ratio you also need to look at the wheel and tire sizes too. The are the last factor in how much force in lbs is applied to the road. For you engineering types the formula for converting the rotational torque in lb-ft at the hub is to divide that number by the radius of the wheel and tire.

As far as using the "get up a go" test - I don't see where it is all that valid of determining how good or bad the drivetrain is. The ECM and TCM computers determine way more of how to handle the "I want to go faster" input and from what I have read, that is where GM is putting most of it's engineering efforts combining AFM, the throttle body, and transmission settings. We must also remember that the accelerator pedal is now connected to a sensor and not to any throttle linkage.

I feel that a better test is to see how the truck handles a load or a trailer.

Great post

crushNchowda · August 26, 2013

Hey all you meatheads going back/forth about this. You're essentially both right, but for all the fuddy duddy's on here who have ZERO experience w/ anything more than 4 forward gears you need to educate yourself. I traded in my 2008 G8 GT that put down 354rwhp fully bolted and it had a 2.92 rear end....oh the humanity!!!!!!! - except it'd SMOKE the tires to obvlivion in 1st and 2nd gear and would fishtail on a WOT 2-3 shift...barely anyone swapped out the gears on these A6' because of the way the tranny splits 'em up its like having a much shorter rear end while still getting good hwy mileage.

The GXP had a shorter rear (I think 3.42 actually on the A6) and they had even more trouble getting the power down and got atrocious mileage on the highway.

You can put a 5.10 rear end in it and it'll still never be "fast" - it is a truck. 3.08 w/ the 6 speed is plenty, believe me.

montecarloman90 · August 26, 2013

Does anyone have an idea when you will be able to order the 3.73 that is the one Thing holding me back from buying a new truck

MikeNH · August 26, 2013

Hey all you meatheads going back/forth about this. You're essentially both right, but for all the fuddy duddy's on here who have ZERO experience w/ anything more than 4 forward gears you need to educate yourself. I traded in my 2008 G8 GT that put down 354rwhp fully bolted and it had a 2.92 rear end....oh the humanity!!!!!!! - except it'd SMOKE the tires to obvlivion in 1st and 2nd gear and would fishtail on a WOT 2-3 shift...barely anyone swapped out the gears on these A6' because of the way the tranny splits 'em up its like having a much shorter rear end while still getting good hwy mileage.

The GXP had a shorter rear (I think 3.42 actually on the A6) and they had even more trouble getting the power down and got atrocious mileage on the highway.

You can put a 5.10 rear end in it and it'll still never be "fast" - it is a truck. 3.08 w/ the 6 speed is plenty, believe me.

Pretty easy to get a truck to run low 14s or even high 13s I bet. That will be fast enough to be fun and probably be a good match against the muscle cars out today on the street/real conditions. As for gearing, I'd always pick the lowest possible gearing for trucks- they weigh a ton more than any sports car. I'll take the hit on the highway MPG to have better power off the line all day long.

BringTheRain403 · August 26, 2013

Hey all you meatheads going back/forth about this. You're essentially both right, but for all the fuddy duddy's on here who have ZERO experience w/ anything more than 4 forward gears you need to educate yourself. I traded in my 2008 G8 GT that put down 354rwhp fully bolted and it had a 2.92 rear end....oh the humanity!!!!!!! - except it'd SMOKE the tires to obvlivion in 1st and 2nd gear and would fishtail on a WOT 2-3 shift...barely anyone swapped out the gears on these A6' because of the way the tranny splits 'em up its like having a much shorter rear end while still getting good hwy mileage.

The GXP had a shorter rear (I think 3.42 actually on the A6) and they had even more trouble getting the power down and got atrocious mileage on the highway.

You can put a 5.10 rear end in it and it'll still never be "fast" - it is a truck. 3.08 w/ the 6 speed is plenty, believe me.

Pull an 8000 pound trailer and then come back and tell me they are both the same. Your car weighs probably 1/3 of what this truck does. Totally different ballpark.

Sent from my Galaxy Nexus using Tapatalk 2

crushNchowda · August 26, 2013

Pull an 8000 pound trailer and then come back and tell me they are both the same. Your car weighs probably 1/3 of what this truck does. Totally different ballpark. Sent from my Galaxy Nexus using Tapatalk 2

More than 2/3 actually. G8 GT's weigh around 4,000 lbs, I don't mind the 3.08, seems fine to me. I won't be trailering much if anything, I will do intake/exhaust/tune and that should be plenty. If I end up towing and the 3.08 doesn't cut it I guess I'd have to look into upgrading, but I really don't think it'll ruin my day lol

BringTheRain403 · August 26, 2013

Until you can't crack 35 going up a hill while towing...

Sent from my Galaxy Nexus using Tapatalk 2

Badass69 · August 27, 2013

Hey all you meatheads going back/forth about this. You're essentially both right, but for all the fuddy duddy's on here who have ZERO experience w/ anything more than 4 forward gears you need to educate yourself. I traded in my 2008 G8 GT that put down 354rwhp fully bolted and it had a 2.92 rear end....oh the humanity!!!!!!! - except it'd SMOKE the tires to obvlivion in 1st and 2nd gear and would fishtail on a WOT 2-3 shift...barely anyone swapped out the gears on these A6' because of the way the tranny splits 'em up its like having a much shorter rear end while still getting good hwy mileage.

The GXP had a shorter rear (I think 3.42 actually on the A6) and they had even more trouble getting the power down and got atrocious mileage on the highway.

You can put a 5.10 rear end in it and it'll still never be "fast" - it is a truck. 3.08 w/ the 6 speed is plenty, believe me.

My old SRT8 Charger had around 400 to the ground by the end... weighed around 4200 lbs and burnt tires through first and second on the street with the 5 speed nag1 and 3.06s in the back..... Funny how after i swapped to the limited slip equipped getrag i kicked myself for not going 373 from a 6 speed challenger instead of 3.06. Same car with the same convertor i had could do at least 2 tenths better 60' time with 3.73 than with 3.06.... oh the humanity. Funny how that has zero to do with a pickup truck with 32" tall tires weighing in at 5500 lbs designed to tow.... but hey, whatever floats your boat. Mall crawler... yep 308s will be just fine.

crushNchowda · August 27, 2013

My old SRT8 Charger had around 400 to the ground by the end... weighed around 4200 lbs and burnt tires through first and second on the street with the 5 speed nag1 and 3.06s in the back..... Funny how after i swapped to the limited slip equipped getrag i kicked myself for not going 373 from a 6 speed challenger instead of 3.06. Same car with the same convertor i had could do at least 2 tenths better 60' time with 3.73 than with 3.06.... oh the humanity. Funny how that has zero to do with a pickup truck with 32" tall tires weighing in at 5500 lbs designed to tow.... but hey, whatever floats your boat. Mall crawler... yep 308s will be just fine.

The G8's get mechanical limited slip from the factory (but that's a different debate) and you WOULD need a shorter rear gear on a SRT8 charger to lower your ET 'cuz they come w/ a 5 speed slush box rather than a proper 6 speed - actually pretty much the same stout unit in the GM trucks- that the G8 has.

If you're not nearing the trailering limits on a reg basis w/ your truck the 3.08's w/ 6 speed is plenty- but you don't drive anything w/ more than 5 forward gears so you don't wanna hear it.

8 speed ZF unit would be even sweeter...

KMGZ400 · August 27, 2013

The G8's get mechanical limited slip from the factory (but that's a different debate) and you WOULD need a shorter rear gear on a SRT8 charger to lower your ET 'cuz they come w/ a 5 speed slush box rather than a proper 6 speed - actually pretty much the same stout unit in the GM trucks- that the G8 has.

If you're not nearing the trailering limits on a reg basis w/ your truck the 3.08's w/ 6 speed is plenty- but you don't drive anything w/ more than 5 forward gears so you don't wanna hear it.

8 speed ZF unit would be even sweeter...

i just towed my loaded 4500lb trailer with my 13' 5.3 with 3.08 and it towed it fine..shifted when it should and held the gears when it should. maybe not as good as the same truck with 3.42's, but it sure as hell towed better then my 2001 silverado with a 5.3, 4 speed and 3.73's

Badass69 · August 27, 2013

My old SRT8 Charger had around 400 to the ground by the end... weighed around 4200 lbs and burnt tires through first and second on the street with the 5 speed nag1 and 3.06s in the back..... Funny how after i swapped to the limited slip equipped getrag i kicked myself for not going 373 from a 6 speed challenger instead of 3.06. Same car with the same convertor i had could do at least 2 tenths better 60' time with 3.73 than with 3.06.... oh the humanity. Funny how that has zero to do with a pickup truck with 32" tall tires weighing in at 5500 lbs designed to tow.... but hey, whatever floats your boat. Mall crawler... yep 308s will be just fine.

The G8's get mechanical limited slip from the factory (but that's a different debate) and you WOULD need a shorter rear gear on a SRT8 charger to lower your ET 'cuz they come w/ a 5 speed slush box rather than a proper 6 speed - actually pretty much the same stout unit in the GM trucks- that the G8 has.

If you're not nearing the trailering limits on a reg basis w/ your truck the 3.08's w/ 6 speed is plenty- but you don't drive anything w/ more than 5 forward gears so you don't wanna hear it.

8 speed ZF unit would be even sweeter...

Ahh another non reading skimmer. I am willing to wager I have more time and accumulated miles with your precious 6 speed.... than you do. No thanks.... you keep it... maybe they will get the gear spread right on the 8 speed And fyi... all SRT8 car chassis anything have had mechanical limited slips since 09.... and didn't need it to skulldrag G8 gt's.. personal track experience there. Not unexpected with the difference in power there. No GXPs in Canada and that's not my fault sorry. The Nag1 only has one overdrive... not two lol. So for available ratios where it matters... it has just as many as the 6L80E and 6L90E.

I'm happy you like your truck... but unfortunately for those that don't we aren't all clueless thanks.