I just bought an LLY...

[Unit453]

Good thread.

You have the Allison 1000.


I would also recommend the Predator. It'll pump up your mileage and give it a nice, light on it's feet feel. I ran the 85 tune without any problems. It does defuel during shifts as a default tune. You wont really notice it all that much. The Predator is the BEST BANG FOR YOUR BUCK handheld tuner. Hypertech is also a good tune. Both will make your truck feel completely different but both offer very nice tunes. I've ran both and ended up keeping both because I liked them equally so much, but both in different ways. Each will give your truck an entirely different attitude and drive-ability. Start out with one of those. Just remember, with an 85 or 90 h.p. tune, you'll be able to ass-rape 90% of traffic on the road. It's hard not to push it all the time.

With your trans. just dont flog it at highway speeds as the shift into O/D was the weak link. Other than that, I never had any issues with the trans. Take care of it and it'll treat you well. Just maintain it and change the spin on filter. Some change it at every oil change but I did mine at around every 10k miles. I also changed my fuel filter at around every 10k miles. You'd be surprised how nasty they'll get.

I personally ran Valvoline Premium Blue synthetic in mine with Transynd as well.

I would also recommend the turbo mouthpiece. I believe the LBZ mouthpiece was a direct swap.

For intakes, S&B is hard to beat, with an 8 layered oiled filter. They make an enclosed airbox to keep the hot, under hood air from getting sucked in. I personally ran an AFE stage II on my LLY but went with an S&B for my LBZ. Both are good systems with quality filters.

MBRP is one of the best exhaust systems out there for the DMAX. You can get a cat delete kit for around $325 or so and it'll sound awesome too.

 

[Crankme69]

Congrads on the new Dmax Forrest!

X2 Let's see some pics

 

[btfarm]

NAPA (know how) gold fuel filter is good.

 

[Pepperidge]

If you are looking for the on engine filters...I've got two Parker/Racor filters I'd let go for $10 each plus actual shipping...I eliminated my factory fuel filtration and no longer need these...

 

[THEFERMANATOR]

NAPA (know how) gold fuel filter is good.

I wouldn't run one of them plastic filters if you gave it to me for free, but that's just me. I run the new RACOR filters which are the same as the new AC DElCO's and I believe FRAM's latest filter is also made by RACOR. As for improvements to your trans, don't waste your money. The only worthwhile gains to be had to a 5 speed are to pull the trans and install a full TRANSGO kit(the bullydog shift kit is a COMPLETE waste of money as well, and will do nothing but leave you lighter in the wallet). You can romp on it pretty hard in 1st to 3rd, but do not get on it on the 3-4, 4-5, or the 5-4 shifts. I haven't driven a PREDATOR tuned LLY, so I can't comment on the defuels of it on an LLY, but I know with the EFILIVE tunes I do I add in extra defuel for the trans's safety. The little bit of time you lose with the extra defuel saves you alot down the road with trans longevity. If you drive it sane, then a 80-90HP tune will be fine so long as your gentle on it during the shifts I mentioned earlier. If you have a heavy foot and flog it alot, stay with a 60HP tune or else your trans will suffer. And avoid switching tunes as much as possible as the ALLISON is an adaptive transmission. If you go to a bigger tune, drive it for awhile working your way up to full throttle to allow the trans to adapt and learn the added HP. If not you won't be happy when you get the P0700 with a check engine light on and are stuck in 3rd gear until you restart it.

 

[Pepperidge]

If you are looking for the on engine filters...I've got two Parker/Racor filters I'd let go for $10 each plus actual shipping...I eliminated my factory fuel filtration and no longer need these...

Got Your PM Forest...That's a helluva deal you got...hope you enjoy many years with that truck...you should have them by Tuesday or Wednesday at the very latest...let me know when you get them...

 

[BIGR]

Congrats on the Duramax Forest, take care of it and enjoy it. It should last you a long time.

 

[btfarm]

NAPA (know how) gold fuel filter is good.

I wouldn't run one of them plastic filters if you gave it to me for free, but that's just me. I run the new RACOR filters which are the same as the new AC DElCO's ...

I wasn't aware that NAPA had gone the way of the plastic filter so I stand corrected. I have WELL over 250k miles on nothing but the Racor so I also am biased. Forest snagged (stole ) Pepp's 2 so he's good to go for 20k or so.

 

[THEFERMANATOR]

NAPA sells WIX, and WIX is the one who makes the plastic filters that have caused countless issues.

 

[treegump]

NAPA sells WIX, and WIX is the one who makes the plastic filters that have caused countless issues.

- Got it.

Also, found out a few things in the few days I've driven it around, and when I unloaded my old truck and put what I could into my new truck.

Someone pointed out that my tail light was out the evening that I received the truck. I went to NAPA w/o investigating it and got a bulb, but before I went into taking my tail light apart to replace the bulb, I checked the fuses. 3 blown fuses, and someone replaced a 15a fuse with a 30a fuse (me thinks the p.o. got tired of the fuse popping because the trailer harness is busted up). I shook the water out of the busted trailer harness and wrapped it in plastic till I can fix it, replaced the fuses with proper, working fuses, and reconnected 2 wires that were snipped/snapped in 2.

Cd player still doesn't work, but the dude that sold the truck to me said he'd look into it. I'm not holding my breath, but I'm a bit hopeful.

Truck seems to idle unevenly...but that could be fuel filter, I suppose (I hope)? I'll find out when I get the new filter.

The shifting or idling while driving also seems to be a bit uneven, but that could be filter issues too - either trans or fuel. I have good fluid level, and its red, so that means good, right?

Oh, and light rattling/vibration on the drivers side, front. I jacked it up and there is no up and down movement, but there seemed to be quite a bit of left to right movement. It appeared that the most movement was happening at the ball joint where the tierod connects to the steering box, before it moves to the next wheel. And that's supposed to be a pivit point, right? Considering there's a ball joint there? Any other thoughts on that? I'd like to put a leveling kit on the front - but if that involves taking apart the front end, I'd rather replace other parts too...so maybe wait a little while? I'm driving a lot less hard, a bit more careful, with this newer automatic truck, than I did with my older truck. And will continue to do so till I replace all the fluids and get more comfortable with it.

Just curious - does it matter what kind of coolant I put in the truck? Oh, and where can I find a manual for this truck? The only one that NAPA sold was for gasoline engines. Is there such a thing as a chilton or haynes or ???? manual that is for duramax trucks?

 

[THEFERMANATOR]

For coolant use DEX-COOL ONLY! DO NOT, and I repeat DO NOT mix coolants. And do NOT use the universal crap at ANY cost. I like ZEREX brand DEX-COOL from NAPA myself, but PRESTONE DEX-COOL is what GM puts in them at the factory. For a manual I would look into finding a set of factory manuals if you want good info. the chiltons and haynes is very generic and poor at best for info anymore. The uneven idle you describe sounds like your describing the infamous idle lope that many of these get due to a sticky fuel pressure regulator. Try some 2 stroke oil in the fuel to see if it smooths out some. Iw ould put a scanner on it and see what the desired VS actual fuel pressure is to confirm what the idle problem is. MOST shifting issues on stock trucks is a partially plugged fuel filter(very common issue with the plastic WIX filters), normally changing out the filter will correct it. Also the trans spin on should be changed out as well every 20K miles or so(I do mine every 10K), and use ONLY an ALLISON filter here. The WIX filters don't always allow full flow and can cause slipping during shifts. The slack in the front end you describe is most likely the idler and pitman arm which is a normal issue on the new trucks just like the older GMT-400 trucks. I would reccomend replacing them with high quality MOOG pieces, installign COGNITO braces, and a set of tie rod sleeves if you do any off road driving in 4X4. Teh rattling is probably the intermediate steering shaft which is a VERY common issue. It is basically just annoying and I haven't ever heard of one breaking(just making noise).

 

[Pepperidge]

For the lopey idle I would put two quarts of universal transmission fluid in the tank... Don't do this often ...one or two tanks should clear it up...I've linked to the thread where a well respected Dmax guru recommended this...it is in one of sfcjones threads about the his fpr and lopey idle...I'm on my phone right now so its hard to find things like this..

 

[btfarm]

There was a TSB with reflash for the '05 CD player that MAY do some good.
TSB 04-08-44-020c, Resolution 04-08-44-020=b
I have had a full and unworking CD player for months but the reflash isn't for '06. If you do go to a dealer for that update, tell 'em you have the 'parking lot surge' (your lope effect) and he may reflash for that for free.
He really needs to give you a vin check so you know all that's been done to it.

:nopics:

Had to do it...:hihi:

 

[WarWagon]

Use fuel injector cleaner for the lopey idle. You run this from a separate 1 gal can and do not put it in the tank.
http://duramaxdiesels.com/forum/showthread.php?t=36198&page=2
The new GM PART # is 88861803

The real problem is likely the fuel pressure regulator needs to be replaced and I did a KISS write up of it. (No need to remove 1/2 the cr@p like alt and ac compressor other write ups have you remove.) Also a leaking injector or FPR, fuel pressure regulator can cause this. Air as well from a cracked filter head or leaking primer o-rings. The o-ring kit is available online for $20.00. There is no tank sock, but, a complicated valve and cup that will suck from the top of the cup till fuel gets low then suck from the bottom. IE low fuel sucks up water.

Trans fluid is for transmissions! It isn't that great and dyes your fuel red for DOT "joy".

The Mouthpiece needs to be changed. Do it while doing the FPR. Block the egr as well. Use a sawzall and open up the fender for the airbox with some ac sealing foam to seal the airbox up. GM also makes some ductwork to help get your engine cold air. Mine had the Aluminum part on it that I cleaned up some - it is a little whiny from the turbo with the aluminum part IMO - but makes a diffrence.

You will want to change all the tail lights etc at 2000+ engine hours and look at the gauge stepper motors and lights to fail. You can get kits or send the cluster out for a rebuild.

I would get a heavy throttle spring and stiffen the bracket for the spring.

 

[THEFERMANATOR]

Use fuel injector cleaner for the lopey idle. You run this from a separate 1 gal can and do not put it in the tank.
http://duramaxdiesels.com/forum/showthread.php?t=36198&page=2
The new GM PART # is 88861803

The real problem is likely the fuel pressure regulator needs to be replaced and I did a KISS write up of it. (No need to remove 1/2 the cr@p like alt and ac compressor other write ups have you remove.) Also a leaking injector or FPR, fuel pressure regulator can cause this. Air as well from a cracked filter head or leaking primer o-rings. The o-ring kit is available online for $20.00. There is no tank sock, but, a complicated valve and cup that will suck from the top of the cup till fuel gets low then suck from the bottom. IE low fuel sucks up water.

Trans fluid is for transmissions! It isn't that great and dyes your fuel red for DOT "joy".

The Mouthpiece needs to be changed. Do it while doing the FPR. Block the egr as well. Use a sawzall and open up the fender for the airbox with some ac sealing foam to seal the airbox up. GM also makes some ductwork to help get your engine cold air. Mine had the Aluminum part on it that I cleaned up some - it is a little whiny from the turbo with the aluminum part IMO - but makes a diffrence.

You will want to change all the tail lights etc at 2000+ engine hours and look at the gauge stepper motors and lights to fail. You can get kits or send the cluster out for a rebuild.

I would get a heavy throttle spring and stiffen the bracket for the spring.

The issue with the regulator is the spring in them is known to break or get weak and not cause a smooth movement. ATF and ashless 2 stroke are EXCELLENT diesel additives. Yes ATF will make your diesel look red, but as far as I know it will not glow red under a blacklight like the dye does. The injector cleaner does help the injectprs some for spray pattern and leaking ball seats if it is deposits causing it, but never heard of it doing anything for a regulator.

 

[treegump]

Sooo much information! So overwhelming!! HAHA :-/ I'm waiting on my filters - allison & fuel before I do my oil. I'm planning on doing them all at one time. A couple of other things I've noticed, that I forgot to mention, was 1 fog light is out (which I found out today is not due to a bad bulb, but rather a busted light with the wire broken too far into the plug to salvage easily), and packed manure/mud EVERYWHERE!! I worked on it for over an hour with a screw driver and got most of the packed mud out. I'lll have to drop skid plates to get the rest. There was even mud packed into the inside of the spare tire (which I tried for a 1/2 hr to get lowered, but couldn't), and on top of the drivetrain. Good times... (I'll try and get the picture of that on here. Oh, and I found an old socket wrench in that mud clutter...) Also, while I was cleaning, I came across what looked like a vent/cooler/radiator of sorts sitting in front of the gas tank. What's it for, and what's the safest way to clean it?

Ok, so I put 2 stroke oil in the tank, and will try the two quarts of universal transmission fluid (does it matter what brand?) for now. Have you guys ever heard of Hotshot Secret? I met at least 1 truck driver (semi-truck) that swore by the stuff. I tried it in the 6.5, and it seemed to help a bit too...

Does it matter what kind of 75w90 synthetic I get for the front and rear diffs? The napa here deals with amsoil and they had "severe gear 75w90", "marine gear lube 75/90w90", and "Gear Lube 75w90"

Bought 15w40 and napa gold oil filter - so I'm set for that. Allison & fuel filter have been ordered. Bought some Zerex, but if the P.O. put something else in, will the Zerex mix well? I know that it would probably be a good idea to flush it, since I don't know what the P.O. did to it, but for some reason, flushing anything just never sounds fun...

I didn't see Dex III transmission fluid, so is it ok to get Dex VI, since it's supposed to cover its predecessors? Also, should I get royal purple, or napa brand, amsoil, or valvoline?(there was another brand...just can't remember) Does it even matter? Do any of these not mix well with others?

Thinking of the Predator...It's my understanding that I need to find an external/separate cluster of gauges? Is there an electronic display that could be used instead of a cluster, or should I stick with dialed gauges? Are they plug and play, or is drilling/tapping/installation involved? I'm thinking it may be worth my time/money to just have a shop install the gauges, and that way it'll look cleaner. Thoughts? (also - any thoughts on brands?)

As far as the mechanical fixes and replacements, I'm going to need a bit more sleep, and time to search everything. Again, I appreciate all of your guys' help! Though I feel overwhelmed at the moment, I'm confident that once the fluids & filters are changed, that it'll be a nice start of improvements.

 

[btfarm]

Right now I'm getting ready (as soon as I get time) to change from Amsoil Severe Gear to another brand of synthetic. It's a bit grabby after several tousand miles and maybe I'm wrong but I have never had that with any of the other brands of 75w90 synthetic (which is what you need to use front and rear). M1, GM 'grape juice', WM Super Tech are some brands.
That's a fuel cooler in front of your tank. Garden hose?
Truck looks good Forest. Spent some time offroad it seems...

 

[THEFERMANATOR]

DO NOT RUN DEXRON VI! It is NOT compatible with all DEX III applications ESPESCIALLY not with the ALLISON(unless you want to drop the trans and build it now rather than later). The seals in the ALLISON before mid year 06 were not compatible with DEX VI and many have failed with bad leaks within a few months of putting it in there. This also applies to other transmissions as well. For reasons that can only be chokked up to greed, GM still says(even though they know otherwise) that DEX VI is fully compatible with applications that called for DEX III. Then again this creates work for them in trans rebuilds to replace seals and such. I use CASTROL DEX/MERC domestic vehicle universal ATF in mine and all of them that I work on, but any dexron 3 compatible fluid will work(just make sure it is NOT DEX VI compatible). Yes that is your fuel cooler in front of the fuel tank. Common rail diesel engines run at very high fuel pressures(23,000+ PSI VS the 6.5's 11,000 on a GOOD day), and that high pressure creates heat. Just spray it out with water is all to get the mud out of it. As for adding stuff to the tank, put in 2 onces of 2 stroke oil per gallon OR the same ratio of ATF per gallon of diesel(I wouldn't do both at the same time myself). For your anti-freeze, so long as it is still DEX-COOL(orange or red in color), you should be fine with a standard drain and refil. If it has any hint of green to it, then flush it out and refil it with a DEX-COOL distilled water mix. I always use distilled water as I have found that tap water will activate the sealant tabs that DEX-COOl contains in it and make a real mess. The DURAMAX will take about 5 gallons(give or take a 1/2 gallon) for a full drain and refil, so keep this in mind when you buy your anti-freeze. I'm partial to VALVOLINE synthetics myself as they are fairly easy to find, and never let me down in my racing days under extreme use.

And as for a monitor type guage, I believe bullydog has a digital type guage pod with an external pyrometer probe as well as the EDGE insight monitor that many use. AVOID teh EDGE juice with attitude set-up as they have had alot of problems with failures on the DMAX and cause all kinds of problems when they go, but the INSIGHT monitor is pretty popular and does alot more than just guages do. They also make a pod that will atatch the INSIGHT monitor to your dash or A pillar in your truck, and it just plugs into your OBD2 port and has one hook-up to a pyrometer probe that you have to drill and tap into the manifold(fairly easy job to do in the truck if you pull the inner fender well out). And while the inner fender well is out, it is a good time to put in the EGR blocker plate as well.

 

[Ed HD]

I see in the one picture your NAPA Carries Torque Drive by Amsoil. That's Amsoil's version of Transynd, and a very good fluid. I changed our 05's fluid with it at 50k, and at 90k now it still looks like new, with 10k filter changes & topping it up. Definitely only use Allison filters. I get my fuel and trans filters from Greg at Lubrication Specialist, and also got a WIF sensor wrench from him. Much easier and safer than using a channel-lock pliers.

I did run the plastic fuel filters for 20k and had no issues, but I have now switched to the Racor's again. Better to be safe than sorry.

These guys are definitely pushing you in the right direction. I concur with a Predator, we have it on our 05, it really woke it up. I also plan on installing some sort of cat-delete or a full exhaust this summer.

Also, truck looks great, and I hope it serves you well. Does it have a cloth or leather interior?

 

[tanman_2006]

Looks nice! I have enjoyed my 06 LBZ and so far it has taken alot of punishment without complaining much. I tow heavy and drive like a bat out of hell right now since I'm busy with work and always in a hurry. So far it hasnt complained more than what i have been told was normal.

I did limp the tranny in 2nd when grossing 38K loaded with hay and getting on it too hard. Got a 2nd gear ratio error or something like that.