Have you installed 3.07 gears in your truck? Kindly step in I have something to ask

[spankybear]

"
spankybear said:
If I can get 15 MPH more with gears and same RPM I think this would be nice. "


You can't (not even remotely close). The vast majority report no notable increase in mileage. There are a few claims of "improved" mileage into the teens, but there has been zero ECU data to support it (along with proof that the speedo was properly recalibrated). If nine owners with 3.07 all say mileage did not change and *one* owner says it tripled, then in all likelihood you will see zero change.

Sigh... do you realize what you just said? I am no math magician but you will get go faster with less engine speed with a the 3.07 ratio vs the stock 3.90 .

QUOTE="Third From Texas, post: 2320860, member: 89394"]


Just keep in mind that surplus pumpkin chunks were being sold by the truckload for $80 ea and the only reason they are rare (supply and demand) is that a couple people out there purchased them all up to *create* the supply and demand rarity. Of note is that when regearing the rear axels on a semi, the parts cost is about $1300 per axel.


[/QUOTE]

I could have also bought gold and sliver cheaper once... What type of comment is that... Do you have any idea how much it cost to run my time machine? Even going back 20 years with my time machine to buy stocks and gold cheap and bring them back to sell isn't enought to cover the operating costs.

So 2600 in parts for gears... you do not add in labor...

May I ask do you have the 3.07 gears installed?

 

[ckouba]

Actually, while spankybear typed MPH, I am starting to think Third read MPG. That makes sense in context.

I haven't driven enough to get real MPG data but I am more than willing to bet I am still well under double digits with my truck even as just a chassis. I would be ecstatic if I got 10 mpg (current van camper only gets ~13 hwy), but will be happy with whatever I get because the other benefits the MTV provides.

 

[spankybear]

Well I am not doing this for MPG... I want less RPM st highway speeds... There is way more to the equation than gearing with it comes too fuel economy. Rolling resistance, aerodynamics, weight, ect... A brick of a heavy truck with huge tires... well

 

[Third From Texas]

Disregarding the mileage prognostications, getting 15 MPH more is exactly what happens when you re-gear. You may or may not see mileage improvement, but you will rev lower at a given speed, or (as stated by spankybear), go faster for a given RPM. That part is just math.

My speedo reads ~48 MPH when my GPS says 60. I have gone 73 MPH per the same app. That is exactly 15 MPH above the OEM rated top speed of 58 MPH. As I stated above, I don't intend to run that fast other than testing if I can (check in that box), but now I will enjoy the benefits of lower motor speed for a given wheel speed.

Chris

Yes, it's been a tough week for my reading comprehension. I saw MPH and responded with regard to MPG (we just had a spirited debate oven on FB last week on the topic).

Yes, of course the speed increases. It's then claims from truck owners that re-gearing lets them get an additional 15 MP *gallon* that I call BS on...

Sorry for the confusion.

 

[Awesomeness]

The 3.07 gears are a 20% change, so you get 20% more speed, and 20% less acceleration and pulling power. This puts 65MPH comfortably low in the RPM range, right after the shift up to 7th gear, and makes for nice cruising. 65MPH feels like less of an obstruction to traffic, and it's nice to be able to get up into the low 70's to pass and stuff.

The loss of 20% acceleration is noticeable, especially in the common scenario where you pull away from a stop light/sign and have to accelerate up to speed up a hill, as the transmission shifts up through the gears - I don't notice it as much offroad, even up steep mountain terrain, because you mostly hang out in those first couple gears. That said, if I was actually using it full of cargo, possibly pulling a trailer, "as intended", it would probably be significantly more painful.

I find people's desire to run the engine at low RPM to be overly cautious. It doesn't make a meaningful difference in MPG, and the engine is meant to be overly reliable. So I don't think you're buying yourself much "failure prevention" with the 3.07:1 gears. If there was a choice (which there isn't), I would prefer gearing that just barely let you drive 65MPH at max governed RPM, like about 3.40:1.

"Is $5000 worth it?" is probably the wrong question. A better question would be "In the list of many expensive possible upgrades to the truck, where does this $5000 upgrade fall?" How you prioritize the installation of 3.07:1 gears will depend a lot on your personal preferences, but there are a lot of things that should be done before worrying about gears (e.g. balancing driveshafts, getting newer tires, fixing leaks and broken things, replacing hoses, etc.). The axle gears are definitely just an optional thing.

 

[Reworked LMTV]

The 3.07 gears are a 20% change, so you get 20% more speed, and 20% less acceleration and pulling power. This puts 65MPH comfortably low in the RPM range, right after the shift up to 7th gear, and makes for nice cruising. 65MPH feels like less of an obstruction to traffic, and it's nice to be able to get up into the low 70's to pass and stuff.

The loss of 20% acceleration is noticeable, especially in the common scenario where you pull away from a stop light/sign and have to accelerate up to speed up a hill, as the transmission shifts up through the gears - I don't notice it as much offroad, even up steep mountain terrain, because you mostly hang out in those first couple gears. That said, if I was actually using it full of cargo, possibly pulling a trailer, "as intended", it would probably be significantly more painful.

I find people's desire to run the engine at low RPM to be overly cautious. It doesn't make a meaningful difference in MPG, and the engine is meant to be overly reliable. So I don't think you're buying yourself much "failure prevention" with the 3.07:1 gears. If there was a choice (which there isn't), I would prefer gearing that just barely let you drive 65MPH at max governed RPM, like about 3.40:1.

"Is $5000 worth it?" is probably the wrong question. A better question would be "In the list of many expensive possible upgrades to the truck, where does this $5000 upgrade fall?" How you prioritize the installation of 3.07:1 gears will depend a lot on your personal preferences, but there are a lot of things that should be done before worrying about gears (e.g. balancing driveshafts, getting newer tires, fixing leaks and broken things, replacing hoses, etc.). The axle gears are definitely just an optional thing.

Larger diameter tires might get around a resultant 3.40:1? I don't know, just asking.

 

[Awesomeness]

Larger diameter tires might get around a resultant 3.40:1? I don't know, just asking.

Possibly. 47" -> 52" is about a 10% change in MPH, so that would get you to about 64MPH.

 

[spankybear]

 

[mauinate]

I just drove my 1088 from Denver to So Cal at 65mph (GPS) and averaged 9 mpg over the course of 3 days based on google maps distances matched with the corrected speedo FWIW. I've never driven one without the high speed gears, but there is plenty of bottom end left too, even when not in mode.

 

[spankybear]

After I done did it... WOW it's a whole another truck. I am now not the guy holding up traffic NOT by choice

Driving it yesterday going 45 ish the trans stayed in 6th. Is this what you guys experience?

 

[Reworked LMTV]

After I done did it... WOW it's a whole another truck. I am now not the guy holding up traffic NOT by choice

Driving it yesterday going 45 ish the trans stayed in 6th. Is this what you guys experience?

Congrats! Do a video showing acceleration and top speed if you can.

 

[Ohiobenz]

"Getting wallet raped by a community member"

Check...

 

[spankybear]

"Getting wallet raped by a community member"

Check...

Oh? do share where one will not get wallet raped having these installed? Just click on reply over there -----v

 

[Third From Texas]

Oh? do share where one will not get wallet raped having these installed? Just click on reply over there -----v

I'd say Reworked who picked up three pumpkins for $2000 is off to a good start.

Remember, these things sold for scrap for like $80 a pop plus freight.

The installation was not mentioned when I told him that he did *not* get wallet raped...

 

[spankybear]

I'd say Reworked who picked up three pumpkins for $2000 is off to a good start.

Remember, these things sold for scrap for like $80 a pop plus freight.

The installation was not mentioned when I told him that he did *not* get wallet raped...

A link would cool where I can get these for those prices... Even an email, or phone number. I am planing on getting another truck and will want to put these gears in.

 

[Reworked LMTV]

A link would cool where I can get these for those prices... Even an email, or phone number. I am planing on getting another truck and will want to put these gears in.

DiverDarrell was his screen name on here.

 

[Third From Texas]

A link would cool where I can get these for those prices... Even an email, or phone number. I am planing on getting another truck and will want to put these gears in.

He's in this discussion. I can't hurt to ask him. I don't have the info.

 

[Ohiobenz]

I paid $4k for new ones.... yup...
Should have bought the gears and rebuilt myself, but time sometimes gets away from me. $3500 to install? Not happening!!

 

[spankybear]

I paid $4k for new ones.... yup...
Should have bought the gears and rebuilt myself, but time sometimes gets away from me. $3500 to install? Not happening!!

You got them in yet?

 

[coachgeo]

I'd say Reworked who picked up three pumpkins for $2000 is off to a good start.

Remember, these things sold for scrap for like $80 a pop plus freight.

The installation was not mentioned when I told him that he did *not* get wallet raped...

as far as I know all the thirds came on axles and they had to be shipped as a whole axle... then dismantled. The couple buyers who grabbed the MRAP axles shipped them to themselves by the truck load. Ton of money involved at a gamble of... "will I find buyers??" and good bit of time (money) disassembling and inspecting them to ensure they are good take off's.

Its called reward for the risks. Yes there is some rapers out there... will admit that too but lets not loose sight of the difference between the risk takers and the rapers.