2021 Chevy Duramax transmission pan replacement (PPE) and oil filter change

wwillson

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The truck (2021 Chevy 3500 Duramax) has 35,000 miles on the clock and I decided to change the trans filter and install a PPE trans pan. I do spill and fills on my transmissions. The 10 speed transmissions don't have drain plugs in their oil pans. This is highly annoying for those who do spill and fills, so I decided to put the PPE pan on because it has a drain plug. The added bonus is the PPE pan holds a gallon more than the stock pan.

The stock pan with the engine off holds about 8 quarts of oil. Rather than try to lower the pan and dump the oil into my drain pan, I used my Mityvac to remove the oil before lowering the pan. I left a couple bolts loose in the other side so I could lower this side enough to get the small suction hose into the pan.



The pan just off the trans. You can see I was able to suction most of the fluid out. The fluid color, with 35,000 miles, is a lot darker than fresh fluid.

Some shots looking up at the transmission.





Some sediment in the bottom of the pan and a thin layer of metallic material on the magnets. The gasket is reusable and has guide pins that help align the gasket when you put the pan back on. I put the magnets back into the aluminum PPE pan.



The new PPE trans pan installed. Removal and installation of the pan is very simple. If someone has a bit of mechanical experience, this job is about a 2 on a 10 scale. There was no hard part, no cross members or anything else needed to be moved. The pan will almost drop straight down, but there is a bit of interference at the back of the trans so the front of the pan needs to be tipped down slightly coming off and going back on. Make sure you understand the refill procedure. You have to get the fluid hot and with the truck level, open the level plug and let the excess fluid drain. It took 14 quarts to bring the level back to the check plug when cold and the engine running. I'm not sure why it took so much and I'd rather not believe the trans was not filled correctly from the factory, ugh. I suctioned about 8 quarts out and the PPE pan holds 4 quarts more than the stock pan. I'm not sure why it took 14 quarts instead of the 12 that I expected to put back in. I will heat the fluid up tomorrow and drain the excess back to the check plug level, but I can't imagine that it will be two quarts.

[edit] I followed GM's procedure to correct the fluid level after filling the trans when cold, except I put an extra step in to see if it's really necessary to torque brake the converter to get the fluid up to 167°F. I drove until the fluid reached the normal temp of 145°F, then pulled the level plug. The fluid went in at about 90°F when I refilled the trans after the pan/filter change. About 0.60 quart came out with the fluid temp at 145°F. Then I torque braked until the fluid temp got to 165°F. Only another 0.15 quart came out. GM says you can hold 1500 RPMs for 15 seconds while torque braking, but I only held 1300 RPMs. I was surprised at how much heat and how quickly torque braking puts into the trans fluid. I only had to hold 1300 RPMs for 15 seconds 5 times to heat all of the trans fluid (around 4 gallons?) from 145°F to 165°F. These engines make a ton of torque and the torque converter was converting all of that power to heat.

The bottom line is that I only got not even a cup of additional trans fluid out of the trans when I heated the fluid from 145°F to 165°F. In the future I will just pull the level plug at 145°F and call it good enough. I see no reason to torque brake the fluid to 165°F, just to get an additional fraction of a cup of fluid out. My $0.02


I took the white bottom cover off the filter and was surprised to see there are two different types of filter media. I grumbled a bit when I saw GM did away with the external spin-on filter, but now they I've seen the size and design of this filter and the fact that GM says to change the fluid and filter every 45,000 miles, I don't think the external spin-on filter is necessary. The filter seems to have one side that is a high flow rock catcher and the other that is a thicker depth filter to catch the smaller particles.

With 4 more quarts of fluid and the transmission past the break-in shedding, I don't have any problem running this fluid (HPL Green Trans Fluid - formulated for this transmission) for 50,000 miles.


A couple close ups of the media.

 
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it's like ford knows 99% of owners wont change the fluid anyways, lol.

Why include a drain plug when nobody is going to change it?

1681010154563.jpeg
 
The truck (2021 Chevy 3500 Duramax) has 35,000 miles on the clock and I decided to change the trans filter and install a PPE trans pan. I do spill and fills on my transmissions. The 10 speed transmissions don't have drain plugs in their oil pans. This is highly annoying for those who do spill and fills, so I decided to put the PPE pan on because it has a drain plug. The added bonus is the PPE pan holds a gallon more than the stock pan.

The stock pan with the engine off holds about 8 quarts of oil. Rather than try to lower the pan and dump the oil into my drain pan, I used my Mityvac to remove the oil before lowering the pan. I left a couple bolts loose in the other side so I could lower this side enough to get the small suction hose into the pan.



The pan just off the trans. You can see I was able to suction most of the fluid out. The fluid color, with 35,000 miles, is a lot darker than fresh fluid.

Some shots looking up at the transmission.





Some sediment in the bottom of the pan and a thin layer of metallic material on the magnets. The gasket is reusable and has guide pins that help align the gasket when you put the pan back on. I put the magnets back into the aluminum PPE pan.



The new PPE trans pan installed. Removal and installation of the pan is very simple. If someone has a bit of mechanical experience, this job is about a 2 on a 10 scale. There was no hard part, no cross members or anything else needed to be moved. The pan will almost drop straight down, but there is a bit of interference at the back of the trans so the front of the pan needs to be tipped down slightly coming off and going back on. Make sure you understand the refill procedure. You have to get the fluid hot and with the truck level, open the level plug and let the excess fluid drain. It took 14 quarts to bring the level back to the check plug when cold and the engine running. I'm not sure why it took so much and I'd rather not believe the trans was not filled correctly from the factory, ugh. I suctioned about 8 quarts out and the PPE pan holds 4 quarts more than the stock pan. I'm not sure why it took 14 quarts instead of the 12 that I expected to put back in. I will heat the fluid up tomorrow and drain the excess back to the check plug level, but I can't imagine that it will be two quarts.

I look the white bottom cover off the filter and was surprised to see there are two different types of filter media. I grumbled a bit when I saw GM did away with the external spin-on filter, but now they I've seen the size and design of this filter and the fact that GM says to change the fluid and filter every 45,000 miles, I don't think the external spin-on filter is necessary. The filter seems to have one side that is a high flow rock catcher and the other that is a thicker depth filter to catch the smaller particles.

With 4 more quarts of fluid and the transmission past the break-in shedding, I don't have any problem running this fluid (HPL Green Trans Fluid - formulated for this transmission) for 50,000 miles.


A couple close ups of the media.

I put an AFE pan on my Cummins Ram for the exact same reasons! No drain plug and extra fluid. It sure is nice when towing.

Just my $0.02
 
The reason there is no drain plug is to force you to drop the pan and, they hope, change the filter.
So stated in my old 1960s/1970s factory maintenance manuals.
 
it's like ford knows 99% of owners wont change the fluid anyways, lol.

Why include a drain plug when nobody is going to change it?
Maybe true but this is a Chevy Duramax.

Holy smokes, you got your truck a month or so before we got ours and you have 3x the miles. That's a lot of heavy towing, the trans will be happy with the extra fluid.
 
There is a similar PPE pan for the Ford 10R60 transmission.

Any concerns with warranty problems due to "modifying" the transmission?
 
The reason there is no drain plug is to force you to drop the pan and, they hope, change the filter.
So stated in my old 1960s/1970s factory maintenance manuals.

Most would argue this is done to modern vehicles to prevent accidental transmission fluid drain by quick lube places and make it less likely to be a DIY maintenance item.
 
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Maybe true but this is a Chevy Duramax.

Holy smokes, you got your truck a month or so before we got ours and you have 3x the miles. That's a lot of heavy towing, the trans will be happy with the extra fluid.

I think this is the 10R80 that was a joint venture between Chev & Ford.
 
FIFY

Engineers do have a sense of humor!

Seriously though, I will drop the pan and change the filter at +50,000 miles and I will pull the drain plug first.
That pan looks well made - was planning to get one for the Rubicon until CarbonSteel pointed out it won’t clear the cross-over pipe that comes with the Pentastar …
BTW: if that’s a 1 of a kind filter - assume you got a spare …
 
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