How to Drain/Refill Automatic Transmission

Personal preference on the gasket, I don’t claim to have any true logical science behind it.

I’d asked the dealership parts guy about the plug washers on the tranny and he’l said they weren’t crush washers. Forget what he said they actually were. Will do some investigation on my own. He had the parts list up based on my VIN.

 

I’ve been a dealership parts guy for 31 years and trust me, a lot of parts guys don’t even know what a crush washer is.

 

Not all parts folks are created equal...if I really want to know for sure I can bug a service person, but they’re not all created equal either obviously. Plus there’s the awkwardness of asking the service guy for info about the service that I’m going to do myself. It’s kinda like asking a girl for her sister’s number...

I do sometimes wish I had access to the full digital parts breakdown.

 

At 55k I did a series of 4 DAFs within about a week.....just to get mostly new fluid in there. I'm at almost 90k now and have done a couple of more just for shits and giggles. I haven't touch the pan or filter.....not yet anyway

 

How’d your drained fluid look? Particularly interested in what came out on DAFs 2-4 since I imagine the darkest stuff came out with the first one.

 

Looked pretty good. Just a little darker than the new fluid with the 1st two DAFs. The 4th one it looked new and might have been a waste in some people's opinion. Keep in mind that WS is notorious for darkening. That is not necessarily an indication of it's condition.

 

So I just drove for about 30 minutes figuring that the system would be plenty warm to try this again. Tried the procedure and got the at light to fire up! But it won’t stop flashing. I think that means it is too warm. Is that right?

 

Thank you man, I thought so but just wanted to confirm. Time for a sandwich and I'll try it again!

 

This is exactly what makes me want to get a scan gauge before executing the DAF...

On the other hand maybe it’s more intriguing to do it the hard way...

 

I don't have a scanguage, and the ODB2 reader I picked up that also reads airbag and SRS codes wont pull the tranny temp. Just checked it again, still flashing. So I get to wait some more!

 

I realized that in prepping to do this I bought replacement crush washers for the fill and drain plug, but not the overflow plug. Anyone know if the overflow plug requires a new washer as part of the procedure? Or is everyone pretty much just cracking the plug to check level and then torquing it back as is? Theoretically speaking it doesn’t do a whole lot of work keeping fluid in given its role. Then again neither does the fill plug.

 

Called the local parts folks and the two washers I have are for the drain and overflow plugs. P/N

$7 35178-30010

35178-30010.

The fill plug, I’m told, has an o-ring, which they say they don’t sell. You’d probably have to order a new plug and the o-ring would be on it.

 

So it's 77 degrees outside. Ive been checking the truck every hour or so and the indicator still flashes. There are no other check engine codes happening, nothing to indicate anything is out of sorts. Any ideas?

 

I don't officially "know" about a new overfill washer BUT I did not replace mine after opening it a few times and it is not showing any signs of leaking. I definitely wouldn't worry about replacing the O ring on the fill plug...

 

I tried one last time and it did go solid! For about 20 seconds before flashing. So it would seem the fluid is just still that warm. Gonna give up on this for now, try again in the morning when it's cool.

 

When you go into temp mode is the light illuminating for a couple of seconds and then flashing? Or flashing right away (before this last time when it was solid)? I can see the interior of a vehicle getting up to 115F in the sun when it’s 80 outside, don’t know if the tranny would do the same right on engine start. One would think since it’s essentially in the shade it would be close to air temp.

 

That's what I thought too. Before it was flashing immediately after the 6 shifts, then I put it into park - went right back to flashing.

Just now, after the 6 shifts I think it was solid - but after I put it in park, it lit up solid. And then was flashing maybe 30 seconds later. Again no codes being thrown. It's wierd. I know I filled it extremely close to perfect. I gotta go drive and pick up a few things, I'll try it again when I get back.

 

If you go drive and come back you know it’s gonna be over the temp range...

 

I meant I’ll check tomorrow morning. I totally said something else there but yeah. Oops