switching to syn trans fluid

[whip]

I have a 1998 Lincoln Continental. I'm thinking about switching to syn transmission fluid. What all is involved when switching? In the past when I've changed fluid, I've drained a few quarts and just replaced what I drained. I'm assuming I can't do that when I switch. How much of the old do I need to drain? Do I need to do a power flush? Any other suggestions?
I don't know much about transmission fluid. What do you guys use?

 

[Joseph_S37]

Your old method of drain and fill will work just fine when making the switch, it will just take a few times to switch majority of the old fluid.

A cooler line flush would waste minimal new fluid as well as replace most of the old fluid, all in one session.

A power flush is not recommended as it can loosen old debris and get it lodged somewhere you don't want it

So either of those two methods will work just fine, it all depends on what you are comfortable ith

 

[duaneb9729]

a lot of ford products have drains on the converter, and once you drain the pan you can just refill it.

I would go to a Lincoln forum and see what they have to say.

 

[dparm]

Do not flush it. If you're anal about running 100% synthetic, you may need to change it two or three times to get all the old stuff out.

 

[sciphi]

Lots of folks on here have had excellent success in doing a cooler line flush. I've done two on my 1999 Buick LeSabre with no harm done to the transmission.

 

[PW01]

I used the "cooler line" method on my Ranger when I switched to M1 ATF

 

[Gary Allan]

There shouldn't be too much fear of stirring things up. The stuff sitting in the pan has been subjected to the full range of fluid velocity that can be attained by the trans. Stuff that could sink out ..sank out ... and stayed there.

There's no reason to think that it will all of a sudden decide to get livelier under the same turbulent conditions, is there?

I like to use the term "exchange". When you say "flush", it appears to automatically be associated with a solvent engine flush.

 

[SteveSRT8]

I have yet to EVER see any local shop doing any sort of 'power' flush. Would somebody please get me a link to the machine?

If you have not changed the filter do that first, then do a line flush. Simple, easy, cheap.

 

[RF Overlord]

Originally Posted By: SteveSRT8
I have yet to EVER see any local shop doing any sort of 'power' flush. Would somebody please get me a link to the machine?
This isn't a "power" flush, but it is one of the more popular "fluid exchange" machines on the market. It uses the transmission's own pump to expel the old fluid and draw in the fresh at the same time.

Link to T-Tech machine.

 

[RF Overlord]

whip, if the fluid isn't brown and nasty-smelling, then you can certainly do a complete fluid exchange, either with a machine as I linked to above, or by the DIY cooler-line method. If the fluid IS already bad, then I would do a few drain-and-fills. When you have the pan off the first time, install a drain plug...makes future changes MUCH easier and MUCH less messy.

 

[Cutehumor]

how did automatic transmissions ever get to 200k without the trans flush??

 

[CharBaby]

Originally Posted By: Cutehumor
how did automatic transmissions ever get to 200k without the trans flush??


I actually think that at one time, auto transmissions were built better, less sophisticated and only 3 speeds or even 4 speeds(less shifting). Engines were(small and big block V8's) and engine torque(300-350 ft.lb) propelled the vehicle and the transmissions just went along for the ride(sort of!) Today, many 4cyl and small displacement V6's require the transmissions(5, 6,7 & 8 speeds) to help the engine make all of it's power in a wider RPM range so that the engines today feel of a larger displacement than one would think and, to also get decent MPG. Now, Im talking some 30 + years ago as compared to today. Back then, you wouldn't think of having a 4 cyl propel a 3000 + lb vehicle or a V6 in a 4500 + lb vehcile but, that how it is today.

 

[RF Overlord]

^^^what Char Baby said^^^

The TH400 in my '68 Buick only has 3 speeds and could be big and heavy and over-spec'd because cars back then were big and heavy and had big low-speed motors. Today's transmissions are smaller and lighter, but have twice the forward speeds so they make more heat. Also, many of them have undersized (if any) coolers, which cooks the fluid faster, requiring fluid with a tougher oxidation spec.

 

[Steve S]

Originally Posted By: Cutehumor
how did automatic transmissions ever get to 200k without the trans flush??
They used to put drain plugs on the torque converter. Though I am not sure if they made 200,000 miles, They were neglected way back then as well.

 

[CharBaby]

Originally Posted By: Steve S
Originally Posted By: Cutehumor
how did automatic transmissions ever get to 200k without the trans flush??
They used to put drain plugs on the torque converter. Though I am not sure if they made 200,000 miles, They were neglected way back then as well.



I thought it was only FORD that put drain plugs in their torque converters. No GM or MOPAR that I have ever owned, IIRC had a drain plug in the torque converter(maybe I didn't know at the time). Or a drain plug in the transmission pan for that matter but, most of the Aisian vehicles that I have owned certainly did. And way back then, alot of the engines didn't make it to 200,000 miles but, many transmissions went from one vehicle to another without a rebuild. I don't know either if they went 200K since few people just like today, change their ATF.

 

[Mike_dup1]

I have done the cooler line flush on many vehicles. A local trans shop here has done it that way 100's of times. As the owner once told me, he likes flush machines and his business went up when the local quick lubes started selling trans flush's. Why? Because many of them use amateurs thinking the machine is fool-proof.

You don't need a machine to exchange the ATF, just drain the pan, R & R the filter (a must). By removing pan you get to inspect trans condition, if pan has lots of sediment/debris than trans wear has occurred, re-evaluate. Disconnect cooler lines at radiator, start engine with trans in park and it will slowly pump out the fluid in the torque converter, while you add ATF to the pan as its comes out into a 5 gallon bucket. I observed the ASE trans pro do that to every one of my vehicles dating back to the 1979 Chevy van that was the first I ever converted over to synthetic atf.

A friend had the atf exchanged this way 3 yrs ago by this trans shop on his 2000 F350 at 100,000 miles. He switched over to AMSOIL ATF and has since put at least another 50,000 miles traveling all over with his 5-th wheel and motorcycle.

 

[whip]

My neighbor told me that the local library has service manuals. What a wealth of info for free! That has lead to another question. The transmission has a drain plug, and according to the service manual, it recommends a thin layer of Teflon pipe sealer. Is this the same as the pipe sealer I get at the hardware store, or is there another type for cars?

 

[unDummy]

Its the same and probably isn't needed. A good washer on the drain plug is usually all that is needed.