flush the fluid thru the cooler first....
Got a few conflicting answers calling around.
Got a few conflicting answers calling around.
Sequence for trans fluid service - pan drop or
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Originally Posted By: eljefino
Pan drop and don't bother with the cooler. Just more splices and failure points.
One car has nice flare fittings and another has a rubber hose and clamp :_)
Pan drop and don't bother with the cooler. Just more splices and failure points.
One car has nice flare fittings and another has a rubber hose and clamp :_)
If your transmission doesn't have a drain plug, see if Dorman makes a pan for it. Dorman's transmission pans have a drain plug for easier ATF changes
pan off is the only way in my shop
Originally Posted By: JR
pan off is the only way in my shop
but if you do both for a full fluid exchange?
Not worth to bother? My fluids are around 25k
pan off is the only way in my shop
but if you do both for a full fluid exchange?
Not worth to bother? My fluids are around 25k
Originally Posted By: slacktide_bitog
If your transmission doesn't have a drain plug, see if Dorman makes a pan for it. Dorman's transmission pans have a drain plug for easier ATF changes
They do, give me an excuse to spend my speed perks. The old one is quite rusty. Around 30 bucks after discounts.
If your transmission doesn't have a drain plug, see if Dorman makes a pan for it. Dorman's transmission pans have a drain plug for easier ATF changes
They do, give me an excuse to spend my speed perks. The old one is quite rusty. Around 30 bucks after discounts.
I also side with just doing a spill and fill with a pan drop. I also second the suggestion of a drain plug, whether you buy a different pan or drill one into your pan. If you have a drill and 12 bucks, you can retrofit your pan: B&M 80250. It seems to get good reviews, but I haven't used one before, so I don't have any first-hand experience.
Pump down the cooler line first which is a quart or two. Then change out the pan fluid and/or filter for another 4 qts or so. Then go back and continue to pump through the cooler line until clear. I only have one cooler line locking clamp to remove the line from the radiator. Then attach a rubber hose to the metal flared fitting. 1st time is always slow. After that, it's a snap. I won't bother with a pan off again until it's time to change the filter again on the 2nd or 3rd fluid change.
Pan drop + filter is my vote. A drain plug for future mess-free drains isn't a bad idea, but otherwise a drop and fill will be good.
On my old F150 I pulled the pan and replaced the filter. Then put on a pan with a drain plug. Then once a week for the next 3 weeks I'd drain the pan, then refill. That got everything out and fluid looked clean as can be.
Yeah, those Dorman pans look very nice. And I think some of my old pans are weeping from corrosion, so this is going to make things very easy. But I know I can never bring my car to an oil change place, they are likely to drain the wrong oil!
Any place that drains the transmission fluid when they're supposed to change the engine oil deserves to pay for that transmission fluid change. It ain't that hard to tell the difference...
What I usually do is remove the return hose from the cooler first, put a piece of PCV hose on it, put it in a bucket/jug then have an assistant start the engine.
Let it run until you see a few small air bubbles and turn off the engine immediately, this will get most of the fluid out of the pan making it a lot cleaner when you drop it.
After you change the filter and reinstall the pan fill approx what you got out total, put another empty container under the hose and start the engine again, let about another 4 qts out before refilling, repeat until either the total capacity is replaced or the fluid comes out the same color as its going in then reconnect the hose/line.
Fill to the low mark and drive the car, then check the hot level. Doing it this way the new fluid pushed the old fluid out without mixing old and new to any real degree and is perfectly safe.
Let it run until you see a few small air bubbles and turn off the engine immediately, this will get most of the fluid out of the pan making it a lot cleaner when you drop it.
After you change the filter and reinstall the pan fill approx what you got out total, put another empty container under the hose and start the engine again, let about another 4 qts out before refilling, repeat until either the total capacity is replaced or the fluid comes out the same color as its going in then reconnect the hose/line.
Fill to the low mark and drive the car, then check the hot level. Doing it this way the new fluid pushed the old fluid out without mixing old and new to any real degree and is perfectly safe.
The way I did it on my Escort (when it had around 165K miles) was to siphon out what I could and replace. I did this a few times a week or two apart. Then I dropped the pan, cleaned the magnets, replaced the filter, and then topped off. I have almost 238K miles on that 21 year old automatic transmission now.
The sequence is irrelevant and is a matter of personal preference.
Originally Posted By: Trav
What I usually do is remove the return hose from the cooler first, put a piece of PCV hose on it, put it in a bucket/jug then have an assistant start the engine.
Let it run until you see a few small air bubbles and turn off the engine immediately, this will get most of the fluid out of the pan making it a lot cleaner when you drop it.
After you change the filter and reinstall the pan fill approx what you got out total, put another empty container under the hose and start the engine again, let about another 4 qts out before refilling, repeat until either the total capacity is replaced or the fluid comes out the same color as its going in then reconnect the hose/line.
Fill to the low mark and drive the car, then check the hot level. Doing it this way the new fluid pushed the old fluid out without mixing old and new to any real degree and is perfectly safe.
Yes, this sounds like good advice and the way I've done it. Honestly if a good shifting trans fails after such a flush you are on borrowed time anyway.
But I also read some old wives tale that you should exchange all the fluid first, then do the filter. Theory being that some debris from that new fluid can clog the new filter. Was on some guys transmission shop site, so take it with a grain of salt. Again the idea being transmission fluid is a detergent and will make all the scary big pieces in your trans come loose and clog things up.
What I usually do is remove the return hose from the cooler first, put a piece of PCV hose on it, put it in a bucket/jug then have an assistant start the engine.
Let it run until you see a few small air bubbles and turn off the engine immediately, this will get most of the fluid out of the pan making it a lot cleaner when you drop it.
After you change the filter and reinstall the pan fill approx what you got out total, put another empty container under the hose and start the engine again, let about another 4 qts out before refilling, repeat until either the total capacity is replaced or the fluid comes out the same color as its going in then reconnect the hose/line.
Fill to the low mark and drive the car, then check the hot level. Doing it this way the new fluid pushed the old fluid out without mixing old and new to any real degree and is perfectly safe.
Yes, this sounds like good advice and the way I've done it. Honestly if a good shifting trans fails after such a flush you are on borrowed time anyway.
But I also read some old wives tale that you should exchange all the fluid first, then do the filter. Theory being that some debris from that new fluid can clog the new filter. Was on some guys transmission shop site, so take it with a grain of salt. Again the idea being transmission fluid is a detergent and will make all the scary big pieces in your trans come loose and clog things up.
I was tempted to get a Dorman pan with the drain plug, but IMO I think spending the extra time to drop the pan is worth it. You'll not only get at slightly more fluid, but it also gives you a chance to clean off the magnetic sludge that is left which is what often causes the various solenoids in the transmission to short out and fail.
Originally Posted By: ford46guy
Originally Posted By: Trav
What I usually do is remove the return hose from the cooler first, put a piece of PCV hose on it, put it in a bucket/jug then have an assistant start the engine.
Let it run until you see a few small air bubbles and turn off the engine immediately, this will get most of the fluid out of the pan making it a lot cleaner when you drop it.
After you change the filter and reinstall the pan fill approx what you got out total, put another empty container under the hose and start the engine again, let about another 4 qts out before refilling, repeat until either the total capacity is replaced or the fluid comes out the same color as its going in then reconnect the hose/line.
Fill to the low mark and drive the car, then check the hot level. Doing it this way the new fluid pushed the old fluid out without mixing old and new to any real degree and is perfectly safe.
Yes, this sounds like good advice and the way I've done it. Honestly if a good shifting trans fails after such a flush you are on borrowed time anyway.
But I also read some old wives tale that you should exchange all the fluid first, then do the filter. Theory being that some debris from that new fluid can clog the new filter. Was on some guys transmission shop site, so take it with a grain of salt. Again the idea being transmission fluid is a detergent and will make all the scary big pieces in your trans come loose and clog things up.
It cant clog anything up, you are removing a good portion of the fluid before dropping the pan and filter then refilling. At that point there is no old fluid in the pan to clog the filter.
When you start the engine again the new fluid gets drawn through the filter but old fluid in the unit continues to go into the jug not the transmission.
When you refill again its new fluid, again nothing to clog, you do not allow any dirty fluid back in the pan. Only when fresh fluid is flowing do you reconnect the line.
You are correct if the transmission cant handle this its was 100% ready to take a dirt nap.
Originally Posted By: Trav
What I usually do is remove the return hose from the cooler first, put a piece of PCV hose on it, put it in a bucket/jug then have an assistant start the engine.
Let it run until you see a few small air bubbles and turn off the engine immediately, this will get most of the fluid out of the pan making it a lot cleaner when you drop it.
After you change the filter and reinstall the pan fill approx what you got out total, put another empty container under the hose and start the engine again, let about another 4 qts out before refilling, repeat until either the total capacity is replaced or the fluid comes out the same color as its going in then reconnect the hose/line.
Fill to the low mark and drive the car, then check the hot level. Doing it this way the new fluid pushed the old fluid out without mixing old and new to any real degree and is perfectly safe.
Yes, this sounds like good advice and the way I've done it. Honestly if a good shifting trans fails after such a flush you are on borrowed time anyway.
But I also read some old wives tale that you should exchange all the fluid first, then do the filter. Theory being that some debris from that new fluid can clog the new filter. Was on some guys transmission shop site, so take it with a grain of salt. Again the idea being transmission fluid is a detergent and will make all the scary big pieces in your trans come loose and clog things up.
It cant clog anything up, you are removing a good portion of the fluid before dropping the pan and filter then refilling. At that point there is no old fluid in the pan to clog the filter.
When you start the engine again the new fluid gets drawn through the filter but old fluid in the unit continues to go into the jug not the transmission.
When you refill again its new fluid, again nothing to clog, you do not allow any dirty fluid back in the pan. Only when fresh fluid is flowing do you reconnect the line.
You are correct if the transmission cant handle this its was 100% ready to take a dirt nap.
Originally Posted By: Trav
Originally Posted By: ford46guy
Originally Posted By: Trav
What I usually do is remove the return hose from the cooler first, put a piece of PCV hose on it, put it in a bucket/jug then have an assistant start the engine.
Let it run until you see a few small air bubbles and turn off the engine immediately, this will get most of the fluid out of the pan making it a lot cleaner when you drop it.
After you change the filter and reinstall the pan fill approx what you got out total, put another empty container under the hose and start the engine again, let about another 4 qts out before refilling, repeat until either the total capacity is replaced or the fluid comes out the same color as its going in then reconnect the hose/line.
Fill to the low mark and drive the car, then check the hot level. Doing it this way the new fluid pushed the old fluid out without mixing old and new to any real degree and is perfectly safe.
Yes, this sounds like good advice and the way I've done it. Honestly if a good shifting trans fails after such a flush you are on borrowed time anyway.
But I also read some old wives tale that you should exchange all the fluid first, then do the filter. Theory being that some debris from that new fluid can clog the new filter. Was on some guys transmission shop site, so take it with a grain of salt. Again the idea being transmission fluid is a detergent and will make all the scary big pieces in your trans come loose and clog things up.
It cant clog anything up, you are removing a good portion of the fluid before dropping the pan and filter then refilling. At that point there is no old fluid in the pan to clog the filter.
When you start the engine again the new fluid gets drawn through the filter but old fluid in the unit continues to go into the jug not the transmission.
When you refill again its new fluid, again nothing to clog, you do not allow any dirty fluid back in the pan. Only when fresh fluid is flowing do you reconnect the line.
You are correct if the transmission cant handle this its was 100% ready to take a dirt nap.
Don't the solenoids and valve body dump back to the pan? This was the argument of the transmission guy. So the older fluid never sees the pan again?
Originally Posted By: ford46guy
Originally Posted By: Trav
What I usually do is remove the return hose from the cooler first, put a piece of PCV hose on it, put it in a bucket/jug then have an assistant start the engine.
Let it run until you see a few small air bubbles and turn off the engine immediately, this will get most of the fluid out of the pan making it a lot cleaner when you drop it.
After you change the filter and reinstall the pan fill approx what you got out total, put another empty container under the hose and start the engine again, let about another 4 qts out before refilling, repeat until either the total capacity is replaced or the fluid comes out the same color as its going in then reconnect the hose/line.
Fill to the low mark and drive the car, then check the hot level. Doing it this way the new fluid pushed the old fluid out without mixing old and new to any real degree and is perfectly safe.
Yes, this sounds like good advice and the way I've done it. Honestly if a good shifting trans fails after such a flush you are on borrowed time anyway.
But I also read some old wives tale that you should exchange all the fluid first, then do the filter. Theory being that some debris from that new fluid can clog the new filter. Was on some guys transmission shop site, so take it with a grain of salt. Again the idea being transmission fluid is a detergent and will make all the scary big pieces in your trans come loose and clog things up.
It cant clog anything up, you are removing a good portion of the fluid before dropping the pan and filter then refilling. At that point there is no old fluid in the pan to clog the filter.
When you start the engine again the new fluid gets drawn through the filter but old fluid in the unit continues to go into the jug not the transmission.
When you refill again its new fluid, again nothing to clog, you do not allow any dirty fluid back in the pan. Only when fresh fluid is flowing do you reconnect the line.
You are correct if the transmission cant handle this its was 100% ready to take a dirt nap.
Don't the solenoids and valve body dump back to the pan? This was the argument of the transmission guy. So the older fluid never sees the pan again?
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