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Discussion Starter · #1 ·
Bought a D-Max. got around 39,000 miles. Just wondering what kind of oil yall recommend. Also any other mantinence that needs to be done. And any tips. Thanks
 

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for oil, either amsoil or delvac 1 (mobil turbo diesel oil). If you don't have documentation when the last time the fuel filter was changed, I would change it along with the allison spin-on if you have an allison.
 

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Discussion Starter · #3 ·
yep. its got the allison. weve had it for around 4 months. weve put around 6k on it. so it due for the regular mantinence. will i loose any fluid when i change the spin on on the tranny? if so where to i add it back in at
 

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the loss of fluid will be minimal. I usually just fill the new filter with tranny fluid before installing it. Also, there should be a magnet on top of that filter that needs to be transfered over. Looks like a big washer and sometimes stays on the tranny itself.
 

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Discussion Starter · #5 ·
Ok sounds pretty straightforward. After we get the tranny and oil filters changed I may attempet the fuel filter. Any tips on that? And can you get Delvac 1 oil at Wal Mart or Autozone? Thanks for all the info
 

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At walmart it would be called mobil turbo diesel oil...it will be a 5w40 oil. Up here it costs about $25 a gallon. As far as the fuel filter, the only thing that I recommend is to use a ziploc or similar bag to drop the fuel filter in after you get it unscrewed so you don't dump fuel everywhere. I don't pull out the fenderliner to do mine, just go from the top with a strap wrench. You can drain the fuel filter before removing, but I would rather just use the bag and not mess with the drain on the filter. (filter would have to be a little loose anyway before opening the water drain on the filter)
 

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Don't forget to check your air filter too. It probably needs to be changed too. I bought my truck with 91K miles, and I doubt the air filter had been changed since 50K.

Also, you may want to change the rear differential fluid while you are at it. It's easy to do, but often neglected. Me? Guilty as charged. I am changing my oil today, so I am doing my diff today as well.

I am a firm believer that these trucks will last a long, long time IF we invest the $$ and time in doing the preventative maintenance.
 

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If your going to change your trans filter, you should also drain the trans fluid in the pan via the drain plug. Once the new filter (dont forget the magnet) and plug are reinstalled, you can add 7 quarts to the trans through the dip stick tube. Use a funnel. After the trans fluid is added, start the truck and check for leaks. Let the trans warm up and check fluid level on dipstick. You may have to add half a quart more. MAKE SURE YOU USE DEXRON VI TRANSMISSION FLUID. The 06 Ali 6 speed comes with DEXRON VI from the factory. DEXRON III will work and some dealerships don't no the difference and are mixing fluids. DEXRON VI is slightly more acidic than DEXRON III. 05 and older Allisons use DEXRON III but I wouldn't risk it, especially if you make a warranty claim and they use that as their arguement.
I run 15W/40 Dino oil in the summer and 0W/40 synthetic in the winter. When my DIC indicates 50% fuel filter and or oil filter life, I change them. I also just changed front and rear diff oils and used 75W90 Synthetic. Both are easy to change...front diff has a drain plug on the lower (drivers) side of the diff and a larger filler plug above it. Use a syphon pump to fill. The rear diff has a drain plug at the bottom 3/8 ratchet will remove it, fill from the side level plug.
 

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I've changed the fuel filter over-the-fender method but find it easier to remove the pass side front wheel ( I remove all the tires and rotate them at this time anyway).Remove the inner fender liner ( use a wedged shaped fork to pop out the plastic retainers) and the fuel filter is easily accessed. Unplug the water sensor and remove it from the bottom of the filter (I use the specialty tool but water pump pliers will work) while holding a small container to catch the fuel that will drain out. I then use my fuel filter wrench to loosen the filter and spin it off. Make sure you account for the old gasket (o-ring) that may stick to the engine. Install new gaskets (o-ring) to new filter before installing on engine. Reinstall the water sensor and plug the wires back together.
 

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Discussion Starter · #10 ·
oops. we went to AutoZone and got the Mobile Delvac. But its 15w 40. Is that the wrong stuff? I think thats the only weight they had in the Delvac. Is Castrol any good?
 

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The LBZ motor should use SAE CI-4 grade oil. 15W40 should be used for ambient (outdoor) air temperatures greater than 5 degrees Farrenheit. 5W40 should be used if ambients are below 5 degrees F.
The new LMM motor (January 07) should use CJ-4 grade. This grade is backward compatible for the older engines (LBZ, LLY, LB7). It has a lower sulfur content which protects the LMM aftertreatment.
 

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Discussion Starter · #12 ·
so the 15w40 will be fine?
 

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Absolutely...and that is a great oil, however, it is a dino oil and not a synthetic. If you live in a really cold climate you may want to consider the synthetic going in to the winter season.
 

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If your going to change your trans filter, you should also drain the trans fluid in the pan via the drain plug. Once the new filter (dont forget the magnet) and plug are reinstalled, you can add 7 quarts to the trans through the dip stick tube. Use a funnel. After the trans fluid is added, start the truck and check for leaks. Let the trans warm up and check fluid level on dipstick. You may have to add half a quart more. MAKE SURE YOU USE DEXRON VI TRANSMISSION FLUID. The 06 Ali 6 speed comes with DEXRON VI from the factory. DEXRON III will work and some dealerships don't no the difference and are mixing fluids. DEXRON VI is slightly more acidic than DEXRON III. 05 and older Allisons use DEXRON III but I wouldn't risk it, especially if you make a warranty claim and they use that as their arguement.
I run 15W/40 Dino oil in the summer and 0W/40 synthetic in the winter. When my DIC indicates 50% fuel filter and or oil filter life, I change them. I also just changed front and rear diff oils and used 75W90 Synthetic. Both are easy to change...front diff has a drain plug on the lower (drivers) side of the diff and a larger filler plug above it. Use a syphon pump to fill. The rear diff has a drain plug at the bottom 3/8 ratchet will remove it, fill from the side level plug.
How much fluid goes into the front and rear differential?
 

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approximately 2 quarts in the front and just under 4 quarts for the rear.
 

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As long as its CI-4 rated or higher oil the 15W-40 is fine for use in your truck. Like said above if your in a super cold climate you may want to drop down to a 5W-40 for cold weather start up.

I would definitely recommend using syntheics in the diffs as most people have no clue how hot that oil gets in these trucks especially when towing.
 

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How often should the diff fluid be changed? I currently have 30,000 miles on my truck, haul a large toyhauler often and still have the orginal fluid in the diff's.
 

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I recommend to my customers to change the factory diff fluid by 25k miles and as early as 5k depending on the service of the vehicle. I would suggest if you tow the 5er that often that you may want to add a Mag Hytec diff cover and switch to the Amsoil Severe Gear oil then from there on change it at 50k miles.

If you would like to use and buy Amsoil at wholesale pricing let me know I can get you set up on the wholesale program and get you a great price on the diff cover and a Trans pan if you have been thinking of adding that due to the towing also.
 

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I keep reading about people using 5w-30 synthetic in the transfer case. Is this the case no matter what year your truck is? If something happens to my transfer case at no fault of the fluid and the dealership finds the 5w-30 will it void the warranty?
 
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