So in the continuing saga of my uninspected car...

I replaced the air filter(couldn't see daylight through it.), cabin filter(couldn't see daylight), changed spark plugs (appear to be original). Of course the car is running perfect now except for some vibration which I suspect is motor mounts. Idle is spot on.

I drained the transmission fluid today. Magnetic plug was covered in dark thick "mud". (I suspect it's never been serviced.). I put in over 3 quarts of trans fluid on refill of Redline D4. Transmission seems to be working fine despite the neglect. This week I will receive the filter and pressure switches.

My question is, should I drive it today and then drain and flush tomorrow? I have seen some threads that people wait a week or a month. This one seems to be really dirty.

Thanks for your guidance and suggestions in advance.

Christopher

 

Lots of threads on this- I would drive it a month and drain again if I were you. If the fluid is original then the 3/4 gear pressure switches are too- probably should change those next month when you do the next refill.

You don't mention the year or mileage of the car so this is very general advice.

 

When I flushed my 6MT, I did a rapid flush. Drain, Fill, Drain, Fill, Drove for 3 days, final drain and fill of GM Syncromesh FM. I would flush that sooner than later and just give your third drain/fill some time.

 

Sorry, it's an 05 with 110,000 miles. Pressure switches and filter are next week.

 

Give it a week or so, do another drain and fill and eventually as you do this more frequently, you can get the fluid back to a pink color.

I think the timely maintenance is key, my 5AT is at almost 300,000 miles and still original, no rebuilds, no pressure switches, not a single issue yet!

 

If any significant 'sludge' or deposits have built up inside the trans, then the drain and fill with 'new' D4 will begin to clean those deposits. Too much or too fast cleaning will try to suspend more depost material in the ATF than can safely be suspended in the existing ATF.

The re-suspended deposits may (or may not) lodge and plug small passages, screens, even the trans filter. That is the general idea behind waiting a bit before doing a second and third drain-and-fill.

In other words, a higher percentage of fresh ATF causes more and faster cleaning of old deposits, caused by the additives and cleaners (detergents) in the 'new' ATF. And D4 is a pretty good synthetic, in terms of cleaning old deposits, and preventing more deposits.

For this reason, some people have suggested waiting as much as 1K miles between drains (and refills), esp when the trans is quite dirty (little or no maintenance). This is to prevent a rapid removal of significant amounts of old deposits at one time, because you are not introducing a large amount of new detergent with a lot of fresh D4 ATF at one time.

And also, if you do not have a filter that you can replace, this is esp. important (you did not state which year trans or if you can replace the trans filter). You could always add an inline filter, as I have done on my Acura RDX.

The other approach is to not wait that long, but still to wait around 200 miles between drains, which is what I did with my own Chevy trans. I did 3 drains at 200 mile intervals, followed by 2 more at 500 miles intervals, and a final drain at an additional 2.5K miles, starting at 110K miles.

The last 3 drains were to remove any large amounts of deposits dissolved by the 1st 3 drains. For my Chevy trans, I was able to do the 1st 3-drains with cheaper Valvoline D6 (full synthetic), followed by 3-drains with D4. Large amount of money involved with the D4 cost, but I simply did not want to wait 2-3K miles between each drain/ fill, to complete the 'total-flush' to completely new fluid.

So I did more drains at shorter intervals, rather than fewer drains at longer intervals.

Yes, the Chevy 4L60E trans is totally different from a Honda trans, but the idea is the same.

As for my own Acura RDX, the trans has been serviced at absurdly short intervals, because of testing with the RedLine Racing fluid. Currently running 1:1 mix of RedLine racing and D4.

 

Thank you so much. This is exactly what I wanted to know. Very very helpful. I think I'm going to take your initial advice and wait a longer interval. I was sick when I saw the amount of sludge on the magnet. It makes a lot of sense to ease out the particulates. I ordered pressure switches and filter but I may go ahead and do a new filter with every flush. It's cheap so why not.

I appreciate the advice and hopefully I can return the favor one day!

 

why redline?

 

I come from a racing background and I've known about redline for years. Quality products tested under racing conditions. It has come recommended by a number of people here who seem to have had success with it. My feeling is that Honda has some transmission issues using their fluid and I understand they even changed the specification at some point. I haven't heard anyone complain of problems with redline d. I'm going with it because of my race car experiences. I wouldn't go with type F for a street car.