Changing Tranny Fluid

[jazbo]

I did a search here and see that I should not flush the tranny. The Caddy dealers promote some sort of back flushing method, but I will not do this. I am taking the car to a caddy dealer - what specifically should I request them to do?

I've got 60k on the car (98 Aurora - same tranny as a caddy). I live in flat-land midwest although I do put the car through plenty of WOT use to keep it clean and have some fun. The fluid life indicator still says 100%. Maybe I shouldn't bother changing it at all???

What are your thoughts?

[adallak]

The fluid life indicator still says 100%. Maybe I shouldn't bother changing it at all???

Exactly! I f the fluide is nice and clean why do you want to change? 68 k is nothing for the tranny if you did not abuse it and it looks like you did not.

[CadiKing]

I did a search here and see that I should not flush the ... The fluid life indicator still says 100%.  Maybe I shouldn't bother changing it at all???

What are your thoughts?

jazbo,

The life monitor is very accurate.

It will probably tell you to change the fluid around 100,k mi.

Pull the dipstick on the trans and smell and feel the fluid.

Is it non-granular...no grit in it?

Does is smell fresh? or does it smell burnt?

Is is red or brown in color?

If there is no grit...

and it smells good...

and it is still red...don't even worry about changing it yet.

when you do, it is not a very difficult job, with plenty of

references here for that.

The dealer will try to get you to spend extra money for nothing.

Flushing the trans stirs up debris, or introduces debris from other

transmissions, and can create future problems,

which the dealer would love to take care of for you. Read $$$

our resident expert assures us there is NO REASON to flush.

just change the fluid when the DIC says so!

[Ranger]

"Back flush" That's even worse than a "flush". That's taking all the crap that's caught in the filter and pushing it back into the trans. Sounds like certain death to me. If you insist on getting any trans service done, just drain and refill. I would specifically tell them NO FLUSH of any kind, and get it in writing.

[jazbo]

Thanks guys. I like the idea of getting it in writing about no flushing. Since it's such an infrequent service, I'll try to be there when they do it and watch. I'm sure they will hate that, but so what. I'm not too much of a do-it-yourselfer. Unless somebody else gives me a good reason, I think I'll just wait for the monitor to tell me to change it.

Just curious - does the monitor suddenly drop from 100 to 0 at some high use point? It's 100% at 60k. What have others experienced?

[Ranger]

The monitor will likely NEVER change unless you overheat the trans.

[Hud]

I asked the same question about a month ago, and the answer was to follow the DIC, that the trans. fluid would outlast the car. Also, the Service Consultant at the Dealership where I purchased the car said the same thing. If personnel at the Dealership say not to change it, It's a sure thing.

[CadiKing]

I have a method of changing the trans fluid that

is fast, cheap, and a no-brainer.

I use a metal can, actually a metal hand sprayer with pump

removed. I hook up a vacuum loosely. I use a 3/8" Clear

plastic tube down the trans fill stick. Drawing the vacuum

on the container allows me to pull the fluid up the hose

without disturbing the car.

I measure and refill with fresh fluid. I only do this in between

regular filter and fluid changes. Keeps the fluid fresh for

just the cost of the fluid and 30 minutes or less of my time.

[KHE]

I have a method of changing the trans fluid that

is fast, cheap, and a no-brainer.

I use a metal can, actually a metal hand sprayer with pump

removed. I hook up a vacuum loosely. I use a 3/8" Clear

plastic tube down the trans fill stick. Drawing the vacuum

on the container allows me to pull the fluid up the hose

without disturbing the car.

I measure and refill with fresh fluid. I only do this in between

regular filter and fluid changes. Keeps the fluid fresh for

just the cost of the fluid and 30 minutes or less of my time.

How do you drain the fluid from the side pan? That's where the bulk of the fluid is. You need to drop the pan and remove the drain plug.

[JasonA]

If personnel at the Dealership say not to change it, It's a sure thing.

I'm not sure I'd take everything a dealership tech says as gospel, but it is true that in most cases, the fluid never NEEDS to be changed.

[Hud]

jadcock-most of the time the dealer is out to make money, and this would be a moneymaker for them. My point is, if they recommend not to change it, it is probably true, otherwise they would have another revenue gernerator.

[JasonA]

Good point!

[CadiKing]

... How do you drain the fluid from the side pan? That's where the bulk of the fluid is. You need to drop the pan and remove the drain plug.

KHE,

Yes, You are correct sir!

This would not work too well on a Caddy trans, but

it does work for many other vehicles.

Hope I didn't mislead anyone..

[Scotty]

Yes Kevin that's true, but don't you think that over time, with the addition of say 2 new quarts each and every oil change that in time that it helps or do you think that's a waste of time, and to just do it all at once?

[KHE]

Either way would probably work but you won't be able to clean the metal particles off the magnet and on a Northstar, you're not going to get much from the bottom pan.

On my Fleetwood and old Park Ave., I am able to pump out about a gallon of trans fluid through the dipstick tube. It makes the job much less messy when the pan is lowered.

[Scotty]

While we are having this discussion, I have been looking at Northstars that have been dropped out at my dealer, it looks like it is possible to get the side cover off without taking the engine out, is it? I know its not an easy job, as it looks like you need to support he engine/tranny assembly and remove an engine bracket.. I would like to remove mine and replace/reseal the gasket. Has anyone done this?

[KHE]

I think it's more involved - here's a link that shows how to replace the input speed sensor with the engine/trans in the car. That repair requires removal of the side cover.

[Scotty]

I think it's more involved - here's a link that shows how to replace the input speed sensor with the engine/trans in the car. That repair requires removal of the side cover.

I remember that, do you have the link? Thanks

[tjtjwdad]

I've ofyen wondered the same thing. Mine has 54K on it. Just recently I had the transmission fluid changed in my Bronco w 154K miles.

I swear, it was difficult to get them to understand why I wanted it changed as opposed to "flushed." Finally they understood what I wanted, along with a new filter (which was the main reason why I wanted it).

Jim

[KHE]

I think it's more involved - here's a link that shows how to replace the input speed sensor with the engine/trans in the car.  That repair requires removal of the side cover.

I remember that, do you have the link? Thanks

I forgot to attach the link....

http://caddyinfo.onedgesolutions.com/howto/pc0717.htm

If it doesn't work, go to the Caddyinfo main page and it is under the FAQ section - transmission.

[Scotty]

Thanks Kevin

[Scotty]

So basically there is NO removing the side pan without dropping the engine. I took a closer look tonight and there is no room to back the pan off... It seems that I have a leak on the side pan... Maybe I will remove one bolt at a time, RTV it, and re-torque it....

[navion]

Mike,

If you have a leak in the side cover and simply retightening the bolts won't cure it, you could try this:

Purchase two of the side pan gaskets (one for a backup plan) and a "filter" & pan gasket kit, Pressure wash the whole area around the side pan. Remove the aircleaner and anything else eaisly removeable. Remove the bottom pan, filters, and drain the side case. Remove all the side case bolts.

Now the hard part, remove & clean all the old gasket from the side pan & transmission. Start from the bottom front and CAREFULLY work the new gasket over the side pan. I believe that there is more room at the bottom for the gasket to slide up before it contatcts the valve body. If careful you MAY be able to work the gasket over the side pan without ripping it. Once you get the gasket worked over the pan, get it into position and bolt it up. Replace the side drain plug, install the two new filters & the bottom pan.

I HAVE NO IDEA IF THIS WILL WORK! It is just that I would try to do it this way before I dropped the engine cradle down!

Now, if you weren't able to get the side gasket into place without ripping it, this is where the second gasket comes in.

After failing with the first gasket. lay the second gasket out on a flat surface. (A piece of window glass works great.) Use an Exacto knife and make a cut in the top of the gasket between tow bolt holes. Make the cut like (>>), an elongated V. If you are good with the knife you could make a cut that looked like a lobe on a jigsaw puzzle. Once the gasket is cut, you can install it on the transmission. On both sides of the cut gasket, use a gasket sealant like Permatex # 3 or Indian Head Shellac. Put the ends together and run all the bolts down snug. Let it sit overnight. Finish tightening the pan the next day. (In this instance I believe that the shellac would be a better choice than the permatex.)

A note on RTV use. RTV is wonderful stuff, and in the right application, unbeatable. The biggest sin with RTV is it's overuse on gasket surfaces. If you are extruding large lobes of RTV on the outside, you can bet that the same thing is happening on the inside also. RTV is different from the old Permatex # 3 and shellac in that it is very cohesive and will not break up if some gets loose inside a peice of equipment. If not caught by a screen or filter, It will go through oil pumps and find it's way through the oil system until it becomes lodged in a small passage. Kind of like a blood clot going to the heart. In sensitive equipment like a automatic transmission, the less sealant used, the better.

Like I said before, I don't know if it will work or not. But I would try this before I dropped that cradle.

With the above being said, good luck if you try it.

If it works, Great! , If it dosen't, ------ (Britt WHO?)

Good luck,

Britt

[Scotty]

Thanks Britt Who!, believe it or not I envisioned that exact same 'fix' where I would CUT the top of the gasket! Thank you for confirming that this concept would work! I am going to definately do that, if your first terrific idea does not work, to slip it over the pan! Thanks