In search of opinions on gear change.

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Vbb199

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So, I'm currently running a 3.42 rear gear in my 89 r1500, with a 31" tire.
It'll tach approx 2200 rpms @ 85 mph, which is a sweet spot for the motor because it's right in the power band.

And likewise, loaded with a trailer, in 3rd gear at a lower speed, it's in the power band.

But I wanna have a little more towing power, and little better takeoff.

I've been bouncing ideas off of several other members thru messaging, but I also wanna hear the forum's thoughts.

Below you'll find what a 3.42, 3.73, 4.10, and 4.56 give you @ 85 mph, on a. 31" tire, With a .7 overdrive.

After doing the math, it seems like a 4.10 really wouldn't hurt anything.
Only Bumps engine speed up 400 rpms in 4th gear @85mph.

I'm currently getting 13mpg on the highway.
I typically will run down large highways at 75-85 mph, but very seldom run 90 or 95 (I'm referring to unloaded).

It seems logical that 4.10 would really make a difference in takeoff and towing ability, and not steal much mpg.


(yes I'm whining/concerned about mpg lol)

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Catbox

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The 3.73's in my truck seem like a best all around compromise.
They have the grunt to get it moving as well as decent enough road manners that keeping up with traffic does not seem like a chore.

The 3.73's in my 1995 Suburban seem also like the best choice as they get its big ass moving when I need it too as well as keeping the tach at a decent pace on the freeway. I usually only go 65 or so on the freeway anyway, to many whack a doo's around here.

While not the same platform, my VW Bug has a Pro Street transaxle that I put into it with a set of 4.12 gears. It is a blast to drive around town, but on long stretches of road it can get old with the very free flowing exhaust I have on it.
 

Vbb199

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The 3.73's in my truck seem like a best all around compromise.
They have the grunt to get it moving as well as decent enough road manners that keeping up with traffic does not seem like a chore.

The 3.73's in my 1995 Suburban seem also like the best choice as they get its big ass moving when I need it too as well as keeping the tach at a decent pace on the freeway. I usually only go 65 or so on the freeway anyway, to many whack a doo's around here.

While not the same platform, my VW Bug has a Pro Street transaxle that I put into it with a set of 4.12 gears. It is a blast to drive around town, but on long stretches of road it can get old with the very free flowing exhaust I have on it.

Appreciate the input. I'm leaning for sure towards 3.73 or 4.10.
 

Grit dog

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Literal "back of a napkin" calc... I like it!

My opinion is, when one is trying to be frugal by driving an old vehicle and concerned about total cost of ownership/operation, have to consider the cost benefit ratio and 9 of 10 times that answer is the most economical solution is don't fix it unless it's broke.

But wants vs needs.

I may spend $12k on a toy that I use 4x a year, but I won't spend a dime on "upgrades" on the old cheap commuter "snack wagon" that hauls the kids around. Only proper maint and repairs. That's my 2c but some would say I waste money on wants vs needs. But I figure I save on the needs to justify the wants.

And I don't think the fuel mileage hit will be prohibitive of doing the deeper gears.
But same thing, estimate 1mpg less x number of miles you drive it (not towing) and it's probably not much.
But I also don't pay attention to fuel mileage in the least.
If I did, we would have a Prius and a Chevy bolt with a rainbow sticker in the back window and not a 300+ hp average across all vehicles in the stable!
 
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Grit dog

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See I would not spend a dime on your snack wagon and justify the 500hp pickup you want to build..."for towing."

So maybe don't listen to my advice...lol
 

Vbb199

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See I would not spend a dime on your snack wagon and justify the 500hp pickup you want to build..."for towing."

So maybe don't listen to my advice...lol


My burb cranks out 330 hp, 385 ft lbs. It'll get up to 65 mph in roughly 9 seconds,(and there's several members that can attest to that) its not just a bone stocker pawpaw truck completely lol, I just dropped a 600hp 700r4 in it that'll bark the damn tires slamming 2nd gear when I get on it, I'm gonna upgrade to roller rockers as well as a msd igintion system when I get the chance. Maybe a performance chip.


, not to mention, since I've cut up and lifted my s10, it's the only thing reliable to drive at the moment! (besides the wife's equinox)
So I gotta eat the cost of filling it up with 93 octane constantly due to the c/r anyway.

If it gets down to like, 10 or 11 mpg on the highway, oh well. That still beats what most carburetors on small blocks on this forum are getting.
I just was fearing like, 8mpg lol
I definitely see your point though about throwing tons of cash at it, but I drive it everyday, I've swapped in 3/4 Ton springs in the rear to do towing as well.
 
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Vbb199

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I won't spend a dime on "upgrades" on the old cheap commuter "snack wagon" that hauls the kids around.


I get the damn kids and wife everywhere they need to go in a GD hurry hahahahah
 

Vbb199

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The the original "soccer mom" truck, but hot rodded, with an exhaust note to match.
Cat I deleted, bypassed with straight 3" pipe straight into a Flowmaster 40, with nothing after it.


Why? Because NOBODY has a suburban that sounds good and goes fast (usually)
 
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The88

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I would 4.10 her. Then if you would ever think of going 33s you should still be happy pappy.
 

Grit dog

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The the original "soccer mom" truck, but hot rodded, with an exhaust note to match.
Cat I deleted, bypassed with straight 3" pipe straight into a Flowmaster 40, with nothing after it.


Why? Because NOBODY has a suburban that sounds good and goes fast (usually)

Well then eff it!
We're past frugal anyway. Gear it down. Make it easier to burn the tires off the back!
This was not even a question in the first place apparently....didn't know it was a sleeper...
But that's why they call 'em sleepers!

Lookin at an 03 Durango tonight as a potential snackwagon 2.0. Almost time to put the wifes car up for the winter again.
I'm sure fuel mileage will suck. It's a 5.9 and may have 3.92s. Think it does.
Version 1.0 last year was a Tahoe. It got 14. No more, no less. Beats driving a little chit box.
 
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Vbb199

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Well then eff it!
We're past frugal anyway. Gear it down. Make it easier to burn the tires off the back!
This was not even a question in the first place apparently....didn't know it was a sleeper...
But that's why they call 'em sleepers!


Lol, well it was, but it wasn't. I'm pretty set I wanna move to 4.10, but I wanted opinions I guess. Just bounce ideas off everyone
 

Vbb199

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Well then eff it!
We're past frugal anyway. Gear it down. Make it easier to burn the tires off the back!
This was not even a question in the first place apparently....didn't know it was a sleeper...
But that's why they call 'em sleepers!

Lookin at an 03 Durango tonight as a potential snackwagon 2.0. Almost time to put the wifes car up for the winter again.
I'm sure fuel mileage will suck. It's a 5.9 and may have 3.92s. Think it does.
Version 1.0 last year was a Tahoe. It got 14. No more, no less. Beats driving a little chit box.


Didn't see your addition, I'm sorry!

In some ways I wished I wouldn't have gotten rid of my. 90 burb, EXACT paint scheme as your pickup.

She was on stock tire, 3.08 ratio, fuel injected, stock motor, stock 700r4 trans, and got 20 - 22 mpg cruising down the highway.

That thing really was a snack wagon, just didn't have any of the luxury options my 89 does.
 

The88

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Now as I look at what you are doing. Do you have to drive 85 everywhere? Maybe try 65 70 hwy cruising? I am now thinking you can go 4.56 if your motor and trans are healthy and don't always cruise at 85. Then you would have a peg leg peeler if you don't throw in an LSD or locker.
 

Vbb199

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Now as I look at what you are doing. Do you have to drive 85 everywhere? Maybe try 65 70 hwy cruising? I am now thinking you can go 4.56 if your motor and trans are healthy and don't always cruise at 85. Then you would have a peg leg peeler if you don't throw in an LSD or locker.
I just run 70-85 mph down HWY 85.
Everywhere else, usually 15 over the speed limit. Hahahahah.

Given the ratios I put on the napkin, any of the alternatives wouldn't affect highway driving too badly.
But 4.56 was obviously the worst.
 

The88

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I should be getting my gears swapped when ever I get home with 4.10s front and rear. And i can tell you now that I already wish i would have gotten 4.56. From what I hear if you want say 4.10 just drop down one more lol.
 

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