Why does Nissan waste money on painting the inside of the trans and engine pans? I asked an indy mechanic and he said "It's so the oil drains off the sides faster." I'm not buying that explanation, especially on a throw- away Sentra. This is on a 90s model; do any current owners notice this practice? For that matter, from any manufacturer, is this a current practice?
Nissan paints the inside of oil pans
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Isn't "throw-away Sentra" and "a 90's model" sort of contradictory?
I'm not sure I'd want paint on the inside of a AT pan, regardless of how durable the mfg claims it is.
I'm not sure I'd want paint on the inside of a AT pan, regardless of how durable the mfg claims it is.
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My atf pan is painted. As is my oil.
I believe the previous poster meant it was cheaper to spray the pans with paint than spray them with another rust preventative.
My trans has 205k on it. Pan looks as new internally. Paint and all. Last pulled at...200.5k miles.
I believe the previous poster meant it was cheaper to spray the pans with paint than spray them with another rust preventative.
My trans has 205k on it. Pan looks as new internally. Paint and all. Last pulled at...200.5k miles.
Originally Posted By: Nayov
Yes steel, now tell me how that is going to rust out bathing in oil. The real question is do other carmakers still paint the inside of oil pans. I've done may ATF pan drops and I don't recall any painted ones.
like GM rotors didn't rust when they were stored outside on pallets
Yes steel, now tell me how that is going to rust out bathing in oil. The real question is do other carmakers still paint the inside of oil pans. I've done may ATF pan drops and I don't recall any painted ones.
like GM rotors didn't rust when they were stored outside on pallets
Jeep oil pans are painted on the inside.
I had to drop a pan last week on a '01 Grand Cherokee and weld in a new bung due to the customer cross threading the drain plug.
I had to drop a pan last week on a '01 Grand Cherokee and weld in a new bung due to the customer cross threading the drain plug.
Interesting, I'd be afraid of a paint failure and peeling paint being pumped through the system until the filter grabbed it, or the screen plugged up. I guess that's not a problem and engineering felt it was better than relying on oil or ATF to protect the internal surfaces of the pan from rust.
Why would a manufacture paint the inside of a oil pan. That is totally ridiculous. If they do, its a dumb oversight. The pan is never going to rust from the inside out, its full of "Rust Preventive" called oil. Peeling paint would be a much bigger problem. I have never seen a painted inside transmission pan, some over spray on it, from outside cover paint, but never painted inside. Simply a bad idea. Cummins N-14 used to put oil pan covers on, to stop rocks from hitting the oil pan. This was a bad idea, it used to hold water in the foam and cause the oil pan to rust out. Other than that, I think a rusted out oil pan would be way behind the rest of the car/truck.
I wish you would tell that to my Dodge Dakota....the trans pan rusted through...only a pinhole but it was below the fluid level.
My Aerostar oil pan rotted from the outside in. IMO aluminum would be a much better choice for an oil pan, and it can be painted too. Add another few $$ to the price of the vehicle and call it a day.
Originally Posted By: Panzerman
Why would a manufacture paint the inside of a oil pan. That is totally ridiculous. If they do, its a dumb oversight. The pan is never going to rust from the inside out, its full of "Rust Preventive" called oil. Peeling paint would be a much bigger problem. I have never seen a painted inside transmission pan, some over spray on it, from outside cover paint, but never painted inside. Simply a bad idea. Cummins N-14 used to put oil pan covers on, to stop rocks from hitting the oil pan. This was a bad idea, it used to hold water in the foam and cause the oil pan to rust out. Other than that, I think a rusted out oil pan would be way behind the rest of the car/truck.
Before assembly....not after.
Why would a manufacture paint the inside of a oil pan. That is totally ridiculous. If they do, its a dumb oversight. The pan is never going to rust from the inside out, its full of "Rust Preventive" called oil. Peeling paint would be a much bigger problem. I have never seen a painted inside transmission pan, some over spray on it, from outside cover paint, but never painted inside. Simply a bad idea. Cummins N-14 used to put oil pan covers on, to stop rocks from hitting the oil pan. This was a bad idea, it used to hold water in the foam and cause the oil pan to rust out. Other than that, I think a rusted out oil pan would be way behind the rest of the car/truck.
Before assembly....not after.
I know on our track engines we would sand/clean up the engine interior, then paint valleys with "Glyptal" to seal the casting, and aid drainback. I have seen oil pan interiors, windage trays, and crankcases as well painted after being smoothed out. Don't know what exactly they are trying to do on a stock engine, unless there is some funky oil control action going on there. Hard to imagine in a low cost stock engine though.
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Quick--someone better let the auto manufacturers know about all of the money they're wasting and failed engines they're about to have from failing paint on oil pans!
Seriously, where do people get this stuff?
I imagine it costs more to mask it off and then prep an unpainted pan for installation than to powder coat the whole thing. While rust may not be an issue when the sump is filled, it's not like a painted oil pan goes straight into the car and is filled with oil? That's not how manufacturing actually works. The pans are probably painted by a vendor somewhere else, sit for a while then eventually make it into an engine. So, you'd have to spend the money to clean the surface rust during installation if you don't paint the whole thing. Makes sense to me.
Seriously, where do people get this stuff?
I imagine it costs more to mask it off and then prep an unpainted pan for installation than to powder coat the whole thing. While rust may not be an issue when the sump is filled, it's not like a painted oil pan goes straight into the car and is filled with oil? That's not how manufacturing actually works. The pans are probably painted by a vendor somewhere else, sit for a while then eventually make it into an engine. So, you'd have to spend the money to clean the surface rust during installation if you don't paint the whole thing. Makes sense to me.
The secondary iron oil pan on my 1989 Nissan 240s SR20DET Turbo performance engine is painted black on the inside, matching the outside. It's smooth as glass and was super easy to clean. No paint pealing after over 25 years in service.
You guys are overthinking all of this. Auto manufacturers do silly things sometimes but this ain't one of them. It's not like they use spray can paint from Walmart, that's designed for outdoor plastic chairs to paint the inside and outside of the oil pans
You guys are overthinking all of this. Auto manufacturers do silly things sometimes but this ain't one of them. It's not like they use spray can paint from Walmart, that's designed for outdoor plastic chairs to paint the inside and outside of the oil pans
Painting the inside of the oil pan makes sense to me now. OTOH ever see paint peeling off the hoods and roofs of cars? Paint can and does fail, that's the only reason why I mentioned it. Obviously it hasn't been a problem yet or we'd have known about it. I've changed a few oil pan gaskets in my day and never saw the inside of the oil pan painted though. So this thread was news to me. I guess a decision was made and the possibility of peeling paint was less of an issue than the inside of a pan flash rusting waiting to be installed on an engine. I'm not going to lose any sleep over the possibility of the inside of my Jeep's oil pan being painted.
I still think aluminum is a better material though, but cost must be a factor as to why it isn't being used as much.
John Deere engines are painted on the inside, along with the oil pans. The reason that was given to me was in their intended use, whether it be farming, industrial, construction, or marine generally involves several months of inactivity.
The idea is that rust would form and damage bearings and other internals when brought out of storage. I have seen several of these torn down and never seen any paint peeling.
The idea is that rust would form and damage bearings and other internals when brought out of storage. I have seen several of these torn down and never seen any paint peeling.
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