FMTV High Speed Gears

[Jcbawn]

I would tread VERY lightly here. Adding a gear will only increase the driveshaft speed, which is already very close to the limits of physics based on all of the testing that the gov't did on several different versions. The last thing I would want to do is speed up the driveshaft even more. Better gears are the much preferred option.

That's interesting, thank you for that information.

 

[coachgeo]

That's interesting, thank you for that information.

Unless you have a driveshaft at horizontal cause your in a 6x6.... or if you choose to install the right kind of CV shaft discovered the study to eliminate the issue. Thus for some this information about ability to change any ratios in the tranny would be very beneficial.

 

[scottmandu]

I would tread VERY lightly here. Adding a gear will only increase the driveshaft speed, which is already very close to the limits of physics based on all of the testing that the gov't did on several different versions. The last thing I would want to do is speed up the driveshaft even more. Better gears are the much preferred option.

There is another 800 rpm or so to be had with regards to driveshaft speed before the equations put things out of the safe zone. The vast majority of LMTV driveshaft issues are the result of worn out slip yokes or imbalanced driveshafts.

However Driveshaft speed is determined by the road speed, so having taller transmission won't result in an increased driveshaft speed unless you are going faster.

 

[coachgeo]

you can swap the planetarys for a higher ratios and valve body mod. Not sure of the setup. I know they used to turn the older Chevy/GM trucks from 5 spd to 6 spds. I think suncoast did them for awhile. Or still does.

Talked too Suncoast other day. They are located not far from where I was raised. Found that a it suprising..... but anyway...

answer is Yes and No..... Gear changes have been done but this was done on the Allison 1000 model... Suncoast ONLY does 1000 model tranny work

 

[coachgeo]

I know you can add a second reverse to the 4000 series. Allison offers 2 different overdrive ratios .64 and .67 in the 4000 series cases. There is .57 available in the 3000 series cases made by a company that replaces the stock .65 ratio in 6th gear. Its their way of more speed with out an overdrive unit. I am sure the planetary gear for that replacement is not much different than the 4000 cases...

Talked to Ted and this is what he says about changing any ratios in these military AWD tranny (M3070 and 3700SP )

The problem is the programming needs to match the mechanical ratios.. Just changing the ratio and not the programming will cause error codes to set and there is no alternate programming available (from Allison) for the 3700 series transmission.. It’s just not going to happen with any kind of factory programming and I doubt anyone has taken time to hack this programming and figure out the correct algorithms used and how to account for a ratio change..​

... You could likely make a mechanical change to a 3700 transmission but again its going to set gear ratio codes and lock you in gear.


​

Ted Keating​

TKT Sales​

(800)-997-4858 – Office x201​

(336)-694-4447 – Fax​

ted@tktsales.com
​

Thus if we found someone to hack the Allison Codes and be able to rewrite them.... or can add side programming thru say an Adrino board which fools all the sensors into reporting to the Allison ECU that everything is normal after a change....... we can then open up the field of playing with with changing to other physical gears or different combination of existing gears to create different ratios.

 

[Aernan]

Coach go. I like your style.

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[blhar15]

There is no such thing as an Allison 3000 series 8 speed. These were only 5 or 6 speed transmissions. The 3070 or 3700 series is a 7 speed

Coach go. I like your style.

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[wheelspinner]

There is another 800 rpm or so to be had with regards to driveshaft speed before the equations put things out of the safe zone. The vast majority of LMTV driveshaft issues are the result of worn out slip yokes or imbalanced driveshafts.

However Driveshaft speed is determined by the road speed, so having taller transmission won't result in an increased driveshaft speed unless you are going faster.

OK, but isn't that what people are looking for? Hey do whatever anyone wants, I never said Don't do it, just tread lightly. If the drive shaft is up to it, go right ahead. Perfect combo would be additional gears and numerically lower axles. A lot of people won't look at the entire picture, just add tranny gears and go.

 

[scottmandu]

Thus if we found someone to hack the Allison Codes and be able to rewrite them.... or can add side programming thru say an Adrino board which fools all the sensors into reporting to the Allison ECU that everything is normal after a change....... we can then open up the field of playing with with changing to other physical gears or different combination of existing gears to create different ratios.

I've wondered if it were possible to get more gears from the 3070 by using different combinations of shifting elements. Most auto manufacturers have done this with minimal hardware changes to the actual transmissions.

 

[Bajated]

Anyone know if you can order these 3.07 chunks online somewhere?

 

[Givinup]

Anyone know if you can order these 3.07 chunks online somewhere?

Bryce wasliek from Florida (look him up on Facebook) has around 40 sets last I checked.

Somewhere on the forum it's mentioned you can buy direct as well. I don't think exact price was named, but the ballpark was $2,500/chunk..I think.

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[wheelspinner]

I just talked to Bryce about these. They are 650 each / exchange (installation is extra if desired) and he has 75 left. He is on his way to a west coast swing, leaving Sunday if anyone wants any between now and 1st of Jan.

 

[steve6x6x6]

Bryce wasliek from Florida (look him up on Facebook) has around 40 sets last I checked.

Somewhere on the forum it's mentioned you can buy direct as well. I don't think exact price was named, but the ballpark was $2,500/chunk..I think.

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WOW, $2,500.00 a chunk.

 

[coachgeo]

WOW, $2,500.00 a chunk...... Guess i need to raise my price.

that must have been everything with install? Other post show the each chunk price around same ballpark as yourself. Hope things are well for you there... fully hurricane recovered etc. in FL.

 

[Givinup]

WOW, $2,500.00 a chunk. I sold 4 new ones a couple of month ago for $550.00 a chunk. Guess i need to raise my price.

It was an expedition portal post. I'll see if I can find it and post the info. It wasn't a resale, but new 3.07s ordered via a driveline company... If memory serves correctly

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[coachgeo]

It was an expedition portal post. I'll see if I can find it and post the info. It wasn't a resale, but new 3.07s ordered via a driveline company... If memory serves correctly

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ahhhh... comparatively to Bryce's and guessing Steve's one's pulled from axles and/or NOS, with brand spanking new... that makes ton more since.

 

[Chism]

that must have been everything with install? Other post show the each chunk price around same ballpark as yourself. Hope things are well for you there... fully hurricane recovered etc. in FL.

Got any more for sale FOB Anchorage, AK? I have an M1083 that could use higher gears.


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[coachgeo]

Got any more for sale FOB Anchorage, AK? I have an M1083 that could use higher gears. .

Not sure why you quoted me. I've nothing to do with sells. PM Steve6x6x6 ... though in the past if recall right he's said he would rather not get into parts..... but instead whole Axles. Also find Bryce Wasielak on facebook and message him. Between the two you'll find something.

 

[Chism]

Not sure why you quoted me. I've nothing to do with sells. PM Steve6x6x6 ... though in the past if recall right he's said he would rather not get into parts..... but instead whole Axles. Also find Bryce Wasielak on facebook and message him. Between the two you'll find something.

Oops, sorry. Hehe. I meant to reply to Steve6x6x6.


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[wandering neurons]

Can anyone PM me Bryce's contact info? I don't play FaceBook (or LinkedIn, or any other social media). I'd like to ask him a few questions about the high speed gears. Thx