What is all needed to run a simple sas with 40s on a k1500?

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I'll probably just roll around in the slowest truck there is for a while
I do have overdrive. My truck is already pretty slow with what I assume is all factory just with a 4 inch lift kit and 33s. I am fine with it being slow. Just don't want it to become a really bad problem. Like taking time to cross a road or something from a stop. After hearing about the cost of gearing, I don't think I'll be doing it for a little while.
 

MrPink

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I do have overdrive. My truck is already pretty slow with what I assume is all factory just with a 4 inch lift kit and 33s. I am fine with it being slow. Just don't want it to become a really bad problem. Like taking time to cross a road or something from a stop. After hearing about the cost of gearing, I don't think I'll be doing it for a little while.
it's because your gearing is not setup for 33's it probably has 3.42 gears in it or could even have 3.08 which would really suck balls. you need 3.73's or 4.11's with 33's or if you go up to 35's 4.56's
 

AirMdwn

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Read these for info on the axles you can use. You're gonna need the Ford axle.
Get a 2nd gen (ribbed) 14 bolt out of a similar year truck or Burban. They bolt right in.
Gears, I would do 5.13s for 40s.
ORD parts for the swap and steering.
Not sure what suspension you want to run, but research leaf spring to keep it cheap.
New drive lines and conversion joints.
Exhaust mod.
Tires are gonna rub.
Brakes are gonna suck.
Look to be in at 5k with parts and shop time.
But it'll be worth it.
 

thegawd

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I used to use this gear ratio : tiresize chart but our transmissions have over drive and this chart is assuming a 1:1 ratio, so its valid for driving in 3rd. overdrive would be a bonus.... there are many other websites that can help figure out what gears you need for the tiresize you want to run but there quite technical and they want to know more than I understand.... I have been unable to find one of the charts with the final drive ratio of 0.7 but like I said there are websites that can do this they just want all the data.. tire size, gear ratios for each gear, ect ect...

40" tires are going to need somewhere around 5.29 gear ratios to stay right in the middle of fuel economy and torque.

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Read these for info on the axles you can use. You're gonna need the Ford axle.
Get a 2nd gen (ribbed) 14 bolt out of a similar year truck or Burban. They bolt right in.
Gears, I would do 5.13s for 40s.
ORD parts for the swap and steering.
Not sure what suspension you want to run, but research leaf spring to keep it cheap.
New drive lines and conversion joints.
Exhaust mod.
Tires are gonna rub.
Brakes are gonna suck.
Look to be in at 5k with parts and shop time.
But it'll be worth it.
Ok. Definitely keeping it cheap on the leaf springs. 5k sounds about what everyone is saying. Thanks
 
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I used to use this gear ratio : tiresize chart but our transmissions have over drive and this chart is assuming a 1:1 ratio, so its valid for driving in 3rd. overdrive would be a bonus.... there are many other websites that can help figure out what gears you need for the tiresize you want to run but there quite technical and they want to know more than I understand.... I have been unable to find one of the charts with the final drive ratio of 0.7 but like I said there are websites that can do this they just want all the data.. tire size, gear ratios for each gear, ect ect...

40" tires are going to need somewhere around 5.29 gear ratios to stay right in the middle of fuel economy and torque.

You must be registered for see images attach
Thanks for this. I was reading something a little while ago and i didn't understand a thing. This is way easier. It sounds like after hearing all this I'll being getting 37s for a while and probably 4.11 or maybe the 4.88. Going to depend on when I get the swap don't and throw the tires on to see what I'm wanting, power or the gas milage. Hopefully the gas prices drop back down here soon.
 

thegawd

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hey no problem! thay was the only real way I fully understood gear ratios was with this chart. Iv been posting that chart for 10 years on the web not ever cluing into the fact that the final drive ratio was incorrect.

If I understood how to input this data into an excel spreadsheet but with the 0.7 for 4L60E, ect or 0.75 for the 4L80E I totally would. unfortunately I have no idea where to start! LMAO
 
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Erik the Awful

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If I understood how to input this data into an excel spreadsheet but with the 0.7 for 4L60E, ect or 0.75 for the 4L80E I totally would.
xc_hide_links_from_guests_guests_error_hide_media

I added a few lower gears and went up to 48" tires for S&Gs.
Link - docs.google.com/spreadsheets/d/1_PCVo7Rv_lCk3dOmK4d4k01GuypIwH43xTta1w7FhZs/edit?usp=sharing

Doh! Had the sharing set up wrong on google docs. It should be open to everyone now.
 
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thegawd

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Hey not bad! it took me a minute to get access to it. You are the man!

I do understand excel but everytime I use it I have to re-teach myself how to do whatever it is I'm doing.

I have made a bunch of operational spreadsheets from business to poultry incubation and incubator calibration..... but gearing..... I dont feel like learning that right now! LMAO

so is there a way to tell what rpms are optimal, fuel economic or high torque? hmmm hmmmm.... the green, yellow and red boxes? people like me, haha understand those boxes more than any of the equations behind it. I wouldn't know how to begin to label that information.

I was thinking that could be copied over from the other graph but that graph is not accurate whatsoever for a final drive ratio so, that's not going to work.

thanks for taking the time to do this Erik!
 
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