Washer for drain plug: Copper, Aluminum, crush?

[LucasDK]

Hi,

In terms of differentials (RWD) and transmissions there is usually a fill plug and a drain plug. I came across the following types:

1. Copper
2. Aluminum
3. Fiber
4. Steel crush
5. Copper crush

By steel and copper crush I mean something like this:

Yesterday, I replaced the oils in my differential and transmission and came across no 2 and no 4. I replaced all plug washers with aluminum washers (no 2).

Are there some general rules for those washers? I would be most happy with just using straight copper washers all the time for all plugs because they are easy to acquire everywhere in all kinds of sizes. In case of "emergency" copper washers can always be annealed again. Am I doing something wrong by using straight copper washers all the time? Anyone with indepth knowledge on this topic?

Lucas

 

[oldhp]

I really like the OE rubber on the backside of the drain plug. But, I've used copper more than any other and never had a problem.

 

[ZeeOSix]

Aluminum or copper washers work well and are what I prefer. I've never had any aluminum washer ever leak, even if used many times over. I stay away from crush washers, but have never had any leak even if reused.

 

[edwardh1]

the toyota dealer washers are really great, some like on transaxle look like a crush washer, others on the oil plug look like flat steel with a thick coating of some kind, really work well, snug time and no leaks.

 

[LeakySeals]

Originally Posted By: edwardh1
the toyota dealer washers are really great, some like on transaxle look like a crush washer, others on the oil plug look like flat steel with a thick coating of some kind, really work well, snug time and no leaks.

Agreed, they used to give them to me free. Yes the larger transmission washer was crush. I'm not sure one size fits all. Is it the bolt, the housing, or both that decides what to use? The truck has a plastic washer on the diff drain bolt. Rubber on the oil drain bolt. Thread sealer on the transfer case bolts.

 

[edwardh1]

the questions is ------why different type of washer in different places, like the Toyota camry v6,
a flat washer with a paper looking coating on the oil drain plug (works great)
and
on transaxle a
"round edge" crush washer (also works great)
both when used one time.
My maxima an oem copper washer that has been reused for years.
I still like the Toyota washers better, great feel when you snug them up, easy to tell when tite but not over tite

 

[bioburner]

Ones that don't leak

 

[andyd]

solid copper can be re-annealed with a torch. Plastic, not so much

 

[BrocLuno]

Ultra-Black on the cleaned threads and the old washer. 30 years now and never a leak

 

[Kira]

The flat, 14mm copper washers on the Saab oil drain plug gave no leaks except for the time I mistakenly used a 15mm.
The flat, 18mm aluminum washers on the Volvo oil drain plug don't leak and feel good as they deform.
The flat, 14mm aluminum washers on Honda oil drain plugs don't leak.
The 7/16" + 1/2" rubber coated washers (GM?) don't leak but do wear out.
I don't recall Dad's Mercury (400-2V) having an oil drain gasket.
The Subaru used a "folded metal" crush washer which didn't leak.
The NP242 transfer cases in Sis' 2 Jeeps had NO gaskets on their drain and fill ports (10mm hex drive).

Questions:
1) Why do they make drains which require gaskets at all? I suppose making them precise enough to be gasket free would add cost.
2) What is the story with those pale blue, hard plastic gaskets included with some new drain plugs? Thay CAN'T work.


I flatten "washer style" gaskets with a sintered brass and diamond cloth and reuse them because I AM that cheap. Kira

 

[LucasDK]

Originally Posted By: Kira


Questions:
1) Why do they make drains which require gaskets at all? I suppose making them precise enough to be gasket free would add cost.


I believe: The drain plugs and washers are

1. Exposed to salt, water and dirt = corrosion. You can see that corrosion tries to work its way toward the center of the gasket
2. Exposed to rough handling by mechanics. If a mechanic somehow scratches the finely machined mating surface, for instance to remove some crud, he suddently made a mark/scratch with a sharp object.

For those reasons the washer/seal will take care of all those "imperfections",

 

[mjoekingz28]

I had an assortment pack from the parts store and the copper washer must've been a heavy thickness or something because it didnt want to deform and I was afraid I'd strip the threads getting it to seat.

 

[MolaKule]

I vote for the copper crusher types.

BTW, you can purchase them for Nissans for $0.49 a piece at the dealer and they DO fit and seal.

Better than going to the Auto Parts store and having to buy a box of washers they may or may not fit.

 

[JustinH]

The toyota ones I have are metal covered in black rubber.

They work fine.

I also have received some felpro ones that are nylon, they work fine as well.

 

[Newreet]

For whatever it is worth, there are also "synthetic" gaskets such as this. I do not know how these compare to the other types of gaskets.

http://shop.advanceautoparts.com/p/needa...411.1/3491560-P