LB7 modification: Daily Driver/Tow Duramax

Thanks for the info guys. What parts can handle what power in the Allison? For instance the need for billet parts, input, strut, etc comes relatively quick in the 47RE. I'd probably go straight to a triple disc converter, but what else do I need do look for in a build? Are there aftermarket valve bodies like with the 47RE? With 315k miles should I look to replace parts the others typically would not? I'd love to build it with you JWhite, I've had a few transmissions apart with friends before, but never an Allison. I'm always up to learn something new. I'll probably start calling around after the holiday season calms down.

Two questions on the fuel system. How do most people regulate the input or do the electric pumps internally regulate? Second, should I consider a draw straw or any bigger lines? I'm not at all familiar with the Duramax fuel system, but I want to get this pump on to help the LBZ pump draw fuel, add some better filtering, and eventually access the higher tunes.
 
Don't worry about hard parts in the Allison, they'll handle plenty of power. Any triple disc converter, popular choices being the Precision ML, and SC1058. Mines a 1056 which is what SC sells as the base in any kit. For clutches, hot new thing is the Raybestos GPZ. Alto red eagles still serve a place, and have worked well for years, but the GPZs are proving better in the c2/c3 packs (especially c3 from the heat).

As for vb, all that needs done IMO is the trim valves (transgo shift kit basically). Mike L did just release new shift valve springs that are supposed to be great. And most kits just come with a shim for the pressure regulator, but MikeL does make a whole new spring that runs even more pressure (that's what I'd buy).

Most lift pumps are regulated by an adjustable spring anymore. My Kennedy pumps are designed different and they don't make more than 5-6psi, just flow a bunch when needed. I recommend a draw straw upgrade, plenty of power has been made without one, but they're really small. I laughed when I saw it.
 
Chris Tobin said:
I would go with Fleece, Merchant or Danville before Firepunk too for an Allison, but the OP asked for a trans builder in Ohio. None of the others are in Ohio. So in Ohio the builder I would trust would be Lavon at Firepunk. I am very confident that he can/could handle anything and building an Allison should be easy for him.

My Allison was built by Jeff Garmon who is also known for his Dodge transmissions and it has held up great with NO problems whatsoever. If quality parts are used a good transmission builder should be able to build you a performance trans with no problems... By the way, mine was built with a SunCoast GMax kit...
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While this is true, there is alot of that goes into a well built trans besides whats in a trans kit. I would get Mark @ Danville to build it or crate it up and have it sent to Mike L.
 
lparrill said:
While this is true, there is alot of that goes into a well built trans besides whats in a trans kit. I would get Mark @ Danville to build it or crate it up and have it sent to Mike L.
Click to expand...


While Mike L. is recognized as one of the original experts, the options for Allison builders has grown tremendously. And I don't see why anyone of the builders mentioned in this thread would not meet the OP's needs.
 
I'm doing a 4,750 mile towing trip in early June pulling a 24ft gooseneck. OH to NM to NY to OH. I'm probably using my LB7 Duramax with 325,000 miles unless it fails me before I leave, in which I'd use old faithful [12v/G56]. I consider myself a rookie, even though I've done a few 2500 mile loaded trips in the past. However, I've never done a long trip like this with a Duramax. I've heard a little talk about oil coolers, fan clutches, etc has got me thinking... is there anything I should do, watch for during, check, or buy before the trip?

Here's a quick run down on my truck:
325,000 mile LB7 Stock trans/axles
25k on new GM injectors
23k on new GM LBZ injection pump
IdahoRob EFI tuning [Optimized Stock, 50hp tow, economy, etc.]
K&N filter element
Muffler removed/piped
EGT/Boost gauges

Pulling a 2014 24ft PJ "Buggy" gooseneck 15,680lb trailer. 1/2 the trip empty, 1/2 with a Dodge Charger/Motorcycle/Toolbox/Shop supplies. I'm guessing the trailer is about 5,000lbs empty and 11-13k loaded.

I'm planning on fresh oil, clean filters, spare fluids, jack, and spare tires. I also need to replace a pitman/idler and two upper ball joints before I leave. I was thinking it'd be a good time to install airbags like I've been wanting to do. I keep telling myself not to over think it because someone out there is pulling a 20ft camper with a Ford Escape, but I've had catastrophic failures out on the road before and I like to be prepared for the worst.

Part of me wishes I would have had the transmission done, but I guess she'll either hold or give me a good reason to replace if I have to limp it back.
 
Truck did great on the trip. I weighed about 12,000lbs for half the trip and 18,750lbs for the other. I ran Rob's 50hp tow tune the whole time and it did very well. The Allison was worry free the whole trip, unlike the nagging 47RE and lockup switch I was plagued with in the past. She was wanting a little more speed at the bottom of the hills in TN and WV, but I can't expect miracles with a relatively stock 330k mile LB7. Never got hot, no issues at all. One small complaint, I found out quickly that my seats are about 1/2 as comfortable as the ones in my Dodge. I think the padding has gone flat and the arm rests are 5-6" too low for me [They almost seem bent] Gotta fix that somehow... maybe swap in new model seats or the jump seat arm rest.

On the transmisson subject. Even though the 2010-2013 Mega cabs make my trousers moist I enjoy driving the Duramax and so does the girl. I've always been sorta "tight" so dumping 30k+ on a truck that I doesn't make me money has always been a bridge I'm reluctant to cross. So, I've called a few shops to get pricing on Allison rebuilds.

Firepunk: Does not do Allisons.
Merchant: They only do 3 steps, 450, 700, and whatever race is. No inbetween builds: $3300 for the 450rwhp build and 12 months unlimited mile warranty. [Single Disc]
Red Line: $3950 for 550rwhp, 2 year craftmanship, 3 year on the converter [Triple Disc].
DHD/All Seasons: $4500 Forgot to ask about warranty.
Toops: Was told to call them by locals, haven't yet.
Limitless Diesel: Was told to call him by MikeL.
Jwhite: I used up my favors with him and I probably owe him a Chiropractic bill.

That's were I'm at with the rebuilds. I couldn't get through to Fleece, I got a voicemail each time. I'll probably call Goerend and see if they have a trusted building near Ohio. Gotta call Suncoast too.

I'm considering spoiling the old girl with a cold air kit. Volant and S&B are on my radar, but [because I'm cheap] I'll be watching for a used one. I'm unsure on a reuseable filter vs the Donaldson Powercore.
 
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LOL don't worry my back is fine.

The redline trans is probably just alto power packs, which is nowhere near $3900 worth of parts/labor IMO. When I talked to Tony at DHD about building one 5yrs ago, he won't do a basic alto clutch build, he uses the gmax kits and such so it'll be bullet proof. With Robs max effort tune I wouldn't trust the MA450 kits with a single disc, not worth the time. I'm sure Evan at limitless will be close to the same price as DHD.

Only way to cheap out is to piece together a kit, but have to know what you're doing. And buy a used converter haha. Goerend does make good converters for the Alli.
 
Well stick a fork in it, this project is over. Truck started to smoke and miss on the last trip back from NY. Only 33k miles on GM injectors and LBZ pump, I couldn't bring myself to screw with injectors again. It was listed for sale and sold a week ago. A new DD/tow/trip truck is in the works. Thanks everyone for the help and conversation on this project!
 
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