Complete rebuild questions.

[beerthirty]

Blew up my rear dif this winter as well as a few other things.

Decided to start tearing into it.

It's a 91 soft top m998 6.5 NA

currently looking at the following.

Upgrade halfshafts to 12k (has the 10k on). My main question is it looks like the alpha hubs are also a good idea. Are the H1 Alpha hubs a good idea or are there better alternatives out there?

Any other modifications I should do while I have the whole vehicle tore down?I plan on replacing every part that shows wear if I can find like new or aftermarket parts. Plan on keeping the 6.5 in this one. As I have another one that I'm looking at turning into a prerunner whenever this one is finished.


Thanks,

 

[TOBASH]

Why would you not upgrade the engine to turbocharged GEP?

Why would you upgrade to 12k axles and boxes when you want your axles to be the weak spot in order to protect the drivetrain?

 

[Mogman]

Unless you install a turbo diesel AND load it up like with armor or a fully loaded shelter you probably do not need the 12K axles, of course ANYTHING can be torn up if you try hard enough, unless you had some problems to begin with you really had to try hard to tear up a diff. I have not heard that many stories about diff. failures that were not maint. related, of course RWH can probably recite a few stories as he has much more experience.
You will need to replace the gear boxes or at least the spur gear in the hubs to install 12K half shafts, going to Alpha gars will be quieter but I would assume very expensive with parts and qualified labor to set them up.
Learning to properly operate the Humvee is as much part of the Humvee experience as owning one.

 

[Retiredwarhorses]

What are Alpha hubs?

 

[TOBASH]

What are Alpha hubs?

Civilian hubs off of a civilian H1 with a Duramax engine. In other words, nothing super special unless they have CTIS. Gobs of money with limited payoff in a non-turbo non-Duramax. IIRC, the gears might be a little quieter with herringbone/slanted meshing....

Sounds like someone has a lot of money burning through their pocket with no idea what to do. Some unscrupulous shoppe is gonna LOVE this guy.

Mogman is on point! " Learning to properly operate the Humvee is as much part of the Humvee experience as owning one. "

 

[Mogman]

Civilian hubs off of a civilian H1 with a Duramax engine. In other words, nothing super special unless they have CTIS. Gobs of money with limited payoff in a non-turbo non-Duramax. IIRC, the gears might be a little quieter with herringbone/slanted meshing....

Sounds like someone has a lot of money burning through their pocket with no idea what to do. Some unscrupulous shoppe is gonna LOVE this guy.

Mogman is on point! " Learning to properly operate the Humvee is as much part of the Humvee experience as owning one. "

I thought the Alpha had helical gears unlike the straight cut gears in everything else HMMWV wise.

 

[TOBASH]

That is what I attempted to describe.

Why in Hell's Bells would a loud military truck with a weak detuned engine need those gears.

 

[rjf189]

I thought the Alpha had helical gears unlike the straight cut gears in everything else HMMWV wise.
View attachment 833446

REV versions of the HMMWV have helical gears.

https://forums.g503.com/download/file.php?id=169138&mode=view

 

[Mogman]

That is what I attempted to describe.

Why in Hell's Bells would a loud military truck with a weak detuned engine need those gears.

I dunno, but I am going through all the 12K hubs I have before installing them on the Dmax M998, If the spur gear is comparable I may install a set.
EDIT a full set from those folks would be about a grand.

 

[Mogman]

REV versions of the HMMWV have helical gears.

https://forums.g503.com/download/file.php?id=169138&mode=view

Is there a big difference???

 

[rjf189]

Is there a big difference???

I will defer to the gurus on the forum, but one would think so, at least insofar as AMG thought it was a good idea to put them in the beefed up trucks for combat purposes. Whether it makes a difference for people like us is a different question (but then again, you have a Duramax, so maybe it would).

 

[Mogman]

I will defer to the gurus on the forum, but one would think so, at least insofar as AMG thought it was a good idea to put them in the beefed up trucks for combat purposes. Whether it makes a difference for people like us is a different question (but then again, you have a Duramax, so maybe it would).

The helical gears should be much quieter than the straight cut gears, not that that would make a HMMWV QUIET!

 

[Retiredwarhorses]

The helical gears should be much quieter than the straight cut gears, not that that would make a HMMWV QUIET!

LOL, my original comment was rhetorical, I know what they meant...they aren’t Alpha hubs, they have been out for some time and are used on the REV, of which I own 3 REV trucks.
AMG didn’t redesign the GH for the Alpha, a lot of what went into it was what they were doing, planning and designed for broader military application for the hmmwv heavies, such as cooled Diffs, Tcase, Wilwood brakes...etc.
The production Dmax in the Alpha while an incredible improvement, was a dumbed down Dmax.

 

[TOBASH]

Is there a big difference???

Well, back in the day when Panzer tanks were a thing, they used flat cut gears and not helical for the top/high gear. They used to break those gears at speed as helical gears will allow several teeth to mesh at once, dispersing the forces. Forgot where I heard this BUT my dad was a tank engineer back during WWII and the Korean Conflict. Maybe he told me? I just can't remember.

With the newer 12K lb. HMMWV's sitting on a platform meant for 5K max, it makes sense that we learned from the mistakes of the Germans in WWII.

 

[Mogman]

LOL, my original comment was rhetorical, I know what they meant...they aren’t Alpha hubs, they have been out for some time and are used on the REV, of which I own 3 REV trucks.
AMG didn’t redesign the GH for the Alpha, a lot of what went into it was what they were doing, planning and designed for broader military application for the hmmwv heavies, such as cooled Diffs, Tcase, Wilwood brakes...etc.
The production Dmax in the Alpha while an incredible improvement, was a dumbed down Dmax.

Yes, as I understand it was tuned for around 300HP

 

[frank8003]

Well, back in the day when Panzer tanks were a thing, they used flat cut gears and not helical for the top/high gear. They used to break those gears at speed as helical gears will allow several teeth to mesh at once, dispersing the forces. Forgot where I heard this BUT my dad was a tank engineer back during WWII and the Korean Conflict. Maybe he told me? I just can't remember.

With the newer 12K lb. HMMWV's sitting on a platform meant for 5K max, it makes sense that we learned from the mistakes of the Germans in WWII.

Was it not the T-34 that came with a big hammer for the driver to get here into gear?
straight cut gears

Hey
double clutch that puppy

 

[beerthirty]

Why would you not upgrade the engine to turbocharged GEP?

Why would you upgrade to 12k axles and boxes when you want your axles to be the weak spot in order to protect the drivetrain?

If I'm going to swap

Why would you not upgrade the engine to turbocharged GEP?

Why would you upgrade to 12k axles and boxes when you want your axles to be the weak spot in order to protect the drivetrain?

Haven't looked at the engine yet to see which variant it is really.
Casting is 12555506 11-19-L so nov-19th year I'm unsure of but in the 2000s I'd assume.

 

[beerthirty]

Civilian hubs off of a civilian H1 with a Duramax engine. In other words, nothing super special unless they have CTIS. Gobs of money with limited payoff in a non-turbo non-Duramax. IIRC, the gears might be a little quieter with herringbone/slanted meshing....

Sounds like someone has a lot of money burning through their pocket with no idea what to do. Some unscrupulous shoppe is gonna LOVE this guy.

Mogman is on point! " Learning to properly operate the Humvee is as much part of the Humvee experience as owning one. "

Doing all the work that I can myself. Just curious if it is worth swapping to alphas or not. From what I'm seeing really only if swapping engines etc would it be worth it.

 

[beerthirty]

From my limited reading today,alphas are helical and weaker than the ones on the hmmwv, but hold better with higher speeds in regards to heat etc and prevent brake swaying when stopping hard.
Also read where someone remachined the geared hubs for uniballs, and basically redid the complete system (not something I'm interested in).

 

[beerthirty]

My engine is a GEP 11-19-L.
Differentials:Rear&front:02-16-87 DANA 1296-271 0 REV-X
Transmission- is the 3L80.

Outside of swapping to the 12k shaft/gears
Also going to
Swap to electric fuel pump
Updated fuel injector pump
New gauges

Longterm:
Looking at a engine and transmission swap maybe this fall. Not sure what yet. 2 years ago I swapped a modded P Pumped DT360 into my F350 dually with a 6 speed at a shop. (happy with the P Pump & mods with it, but pretty sure now that I'm getting into doing things myself, the P Pump was unnecessary as the A pump probably would've been fine with the S300 turbo fuel wise). I like the DT360, but haven't looked into if it would fit without heavy modification(likely will) and what it'd all entail. Not to interested in the common Cummins/dura swap.