Does anyone know the capacity for the front differential? Also is there a thread on here of all the fluid capacities for every year duramax?

Thanks,
Rich

Capacities approx:

*Allison: 8-11 qrts
(8 qrts drain plug – 11 qrts drop pan)

*Transfer case: 2 qrts

**Front axle: 2 qrts
**Rear axle: 4 qrts


;)

Does anyone know the capacity for the front differential? Also is there a thread on here of all the fluid capacities for every year duramax?

Thanks,
Rich

Rich here is a little sheet I made up and keep on file for customers with Dmax's.

Your Duramax in a Chev/GMC pick up truck will take 10 qts (2.5 gal) of oil in the engine with the filter change. With dual bypass it will take 11.5 qts. Recommended oil for pre DPF trucks is 15W-40. The Newer 2007.5 and up trucks that have a DPF need the CJ-4 rated oil.

The Allison transmission will take 7.4 qts (2 gal) for a pan drain with the spin on filter change if you have the OEM stock pan. Get 5 gal if you are doing a flush to get the oil into the torque converter. For the Allison you will want the Torque Drive Fluid if you are going to use the Amsoil. A Deep pan will take more fluid depending on the brand pan. Most pans will take 3.5 more qts. I think an ATS deep pan takes 4.5 qts

The rear diff will take just short of 4 qts of 75W-90 gear oil with the stock cover. If it’s an aftermarket such as the Mag-Hytec it will take 7.5 qts. If you are doing a lot of towing or hauling heavy loads I recommend you use 75W-110 in the rear diff.
The Amsoil Product for this application is the “Severe Gear” oil.

If you have 4wd:

The Front diff will take just short of 2 qts 75W-90

The transfer case will take 2 qts of either ATF or 5W-30 synthetic motor oil depending on which way you want to go. If you use the over fill method through the speed sensor it will take 3 qts.

There is nothing really special except with the Trans spin on filter. There is a magnet on the top of the filter that will need to be cleaned real well and put back on top of the new filter before installing it. Also there are magnetic drain plugs in the diffs that need to be cleaned as they will have shavings on them.

On the fuel filter make sure you don’t cross thread the plastic WIF sensor. It’s easiest to take out the inner fender well on the pass side to get at the fuel filter its 8 plastic clips.

Dirtbikindad393 - Great information, saved me a ton of time. Each time I do a fluid change, I have to look it up again. Just found this post. Thanks.

Capacities approx:

*Allison: 8-11 qrts
(8 qrts drain plug – 11 qrts drop pan)

*Transfer case: 2 qrts

**Front axle: 2 qrts
**Rear axle: 4 qrts


;)
I'm pretty sure I put 3 qts 5w-30 in the t-case and 3 qts. in the front diff along with 4 in the rear of severe gear.

Dane, could you pls add the torque specs for each, will save noobs like me a lot of time ;-)

Op, a funnel and long clear hose works wonders in filling the fluids,
if you going to pump, warm them up in a bath of hot water to get to flow faster

I put in a little more than 2 quarts then it ran out of the fill hole slowly.

I have heard that doing a drain/refill on the differentials can sometimes cause the seals to start leaking for some reason like the factory fluid has an additive to prevent seals from going bad. Anyone else heard this? I dont submerge my axles at all in water so I just Make sure they are topped off with fluid, but I am curious to know if the leaking can occur from this...

On the front diff, when you drain it.. it comes out disgusting looking. kinda grey and cruddy. get an extra bottle of lube and Flush it out before adding two new quarts. It's a normal condition.

I have heard that doing a drain/refill on the differentials can sometimes cause the seals to start leaking for some reason like the factory fluid has an additive to prevent seals from going bad. Anyone else heard this? I dont submerge my axles at all in water so I just Make sure they are topped off with fluid, but I am curious to know if the leaking can occur from this...

Never heard of this happening. I have changed mine with no issues and many customers have done theirs with no issues.

Ok I was just wandering. I thaught I heard somthing like that and was curious. I guess I will change mine soon cause I have ran it at the strip a few times and pulled once and I tow alot so might be a good idea.