High mileage auto tranny - change fluid and filter or leave alone?

[4X4XFD]

2002 FX4 4WD (factory pkg) 4.0L, 5R55E tranny, L/S rear diff, elect transfer case. I bought the truck used. Had just under 70K miles on it and soon after getting it I had the local Aamco shop change the fluid and filter (drop pan, change filter, refill...no flush). It now has 152K and I'm wondering about whether or not to do another fluid and filter change myself.I hear some say to just leave a high mileage auto tranny alone if it's not ever had any service. Is it worth the potential risk in this case for me to drop the pan and refill? Filter change optional. If so, what amount of fluid should I expect to replace?

 

[4.0blue98]

I try to do a pan drop and filter change every 40-50k in my 98 with the 5R55E. I went about 70k one time. Its got 203k on it now. I definitely wouldn't flush but yours has had service. I don't think you'd have an issue. Mine took almost exactly 4 quarts.

 

[alwaysFlOoReD]

If you have problems after a fluid and filter change, it was going to happen anyway.

 

[DILLARD000]

Have here near identical drivetrain+frame here in a 2001 SportTracJob2;
260kMiles on original V6~4.0L~SOHC Engin \ 5r55e Trans \ 1354 4x4TCase \ 4.10 Diffs LS Rear + OS Front.

Definitely do NOT let a shop "power flush" the Trans, using a pump machine & tank of questionable ATF; lots of horror stories there.
A full Tranny service every 33kMiles\4years is generally a good idea: BandAdjust + PanDrop + New Filter + New PanGasket + 5~7qts MerconV.
If you're truely leary of that, at least handpump ~1qt up thru the Trans DipTube & refresh with a quart of new MerconV,
then drive 50~100miles & repeat the process until you're satisfied the ATF has been fully renewed.
I do this 1qt MerconV ATF refresh, using AmsOil#SSMV or Redline#HighTemp (whichever is cheaper),
1qt new MerconV = 3/4 qt refesh for Tranny + 1/4 qt refresh for SteeringReservoir,
every 5kMiles\6mths along with the routine Engine Oil+Filter change.

Hope this helps.

 

[Josh B]

Have here near identical drivetrain+frame here in a 2001 SportTracJob2;
260kMiles on original V6~4.0L~SOHC Engin \ 5r55e Trans \ 1354 4x4TCase \ 4.10 Diffs LS Rear + OS Front.



Hope this helps.

 

[Chapap]

If you have problems after a fluid and filter change, it was going to happen anyway.

Completely agree, but I have learned to think that you should just let trannys go till they die. I've had two cars that I changed fluid on, and both resulted in rebuilds shortly after. Then I've had three cars that I really wanted to change the fluid on, but remembered what happened to those two cars... and they ran to 200-300k miles. The 300k mile one was a 92 Caravan. Zero engine drivetrain repairs except a timing belt I think.

Tranny flushes *should* be normal maintenance like any other fluid, but if truly was it wouldn't be a heavily debated thing. I generally only consider flushes as a hopeful fix to avoid a rebuild.

 

[rubydist]

My experience is also with those miles just drive it until it dies. On the Ford trans, there is more risk of problems after the pan drop / filter change than without, in my experience.

 

[4X4XFD]

Some how I had it in my head to do the fluid/filter change every 70K miles. But I don't know where that came from now. My bad for not servicing it more frequently. It's had some odd shifting issues the past couple of years. It can shift real hard (thudding?) from 1st to 2nd and then going into OD. The other gear shifts seem ok. Doesn't happen all the time and I've learned to lessen the chances by accelerating slowly. Maybe this is a valve body issue? Seems to have a minor pan gasket leak and I first started experiencing the hard shifting events when the fluid level got low

 

[19Walt93]

Changing transmission fluid does not cause failures, lack of maintenance does. A customer had us service his car- just an LOF, nothing major- and a month later a tierod separated. He blamed the failure on the service, not on the years of neglect before it. I chewed out the tech for not shaking the tierods while he was under the car anyway, if he wanted to do half assed work he should have applied at Jiffy Lube, but he didn't cause the failure.
I changed the transmission fluid in my 11 Ranger every 30,000 miles and did the transfer case fluid at the same time. Per the manual, I used only Mercon spec fluid in the transfer case- in later years Ford sold it only as transfer case fluid for stupid money so I used Valvoline's Mercon instead. Drop the pan and replace the filter, don't bother with trying to suck it out through the dipstick tube. I change the fluid in my Escape every spring because it's just a drain and refill. If the fluid is "too clean" you'll never know, if it's not clean enough you'll find out.
While you're under there, flush out the brake fluid, too.

 

[Chapap]

Changing transmission fluid does not cause failures, lack of maintenance does. A customer had us service his car- just an LOF, nothing major- and a month later a tierod separated. He blamed the failure on the service, not on the years of neglect before it. I chewed out the tech for not shaking the tierods while he was under the car anyway, if he wanted to do half assed work he should have applied at Jiffy Lube, but he didn't cause the failure.
I changed the transmission fluid in my 11 Ranger every 30,000 miles and did the transfer case fluid at the same time. Per the manual, I used only Mercon spec fluid in the transfer case- in later years Ford sold it only as transfer case fluid for stupid money so I used Valvoline's Mercon instead. Drop the pan and replace the filter, don't bother with trying to suck it out through the dipstick tube. I change the fluid in my Escape every spring because it's just a drain and refill. If the fluid is "too clean" you'll never know, if it's not clean enough you'll find out.
While you're under there, flush out the brake fluid, too.

What would you do at 100-200k miles and never had a fluid change?

 

[19Walt93]

What would you do at 100-200k miles and never had a fluid change?

Yes and I'd repeat it after a couple of months. Clean fluid will not hurt anything. The person who drove that far without a trans service needs a good solid head tap with a wooden mallet.

 

[lil_Blue_Ford]

I was worried when I did fluid and filter on my 92 with unknown maintenance and around 150k. While I was in there I did a shift kit and valve body mods and when I put it back together I attempted a band adjustment. Couldn’t get that just right because of rust, but I got it closer than it was. I had worried about finding some “glitter” in the bottom of the pan along with some sludge, but that trans couldn’t have been happier. Went from mushy shifts and all to nice crisp shifts and hitting the gas too hard from a stop could easily break the back tires free (l/s). Night and day, wouldn’t hesitate to do it again.

 

[Chapap]

Yes and I'd repeat it after a couple of months. Clean fluid will not hurt anything. The person who drove that far without a trans service needs a good solid head tap with a wooden mallet.

It might be more of an issue of if you want it to be right, or just want it to work. In my (limited) experience, dirty tranny fluid is a perfectly fine "bandaid" for whatever problems may be in there.... If both methods make it to a quarter mil miles, why risk it (is my reasoning)?

For example: My old explorer was perfectly fine. I didn't like the gunk in the coolant so I did a flush. That broke up the fix a leak and I wound up uncovering a blown head gasket. That's not quite the same since the HG can hurt other things, but the tranny just gets swapped out. It sounds like OP's tranny is a perfect candidate for a flush. I wouldn't want it shifting hard in 1st and OD. I'd just plan on a worse problem getting uncovered and needing a new tranny.

 

[DILLARD000]

...past couple of years. It can shift real hard (thudding?) from 1st to 2nd and then going into OD
...learned to lessen the chances by accelerating slowly
...valve body issue?
...minor pan gasket leak
..started experiencing the hard shifting events when the fluid level got low

Typical slipping as 5r55e Trannys age; possibly blown VBTopGasket, leaky ValveSeats\ORings, failing Solenoids.
I'd first try retorqing the Tranny PanBolts to fix that "minor" leak,
then HandPump ~24oz from DipTube, refill with a bottle of LucasTransmissionFix\LTF; this is just HighViscoity ATF that can help smooth shifting.
Also check DipTube where upper tube slips into the lower tube then into the Tranny housing; this ORing joint often leaks;
giving the tube a few gentle love taps from the top end with a socket & 1/.2" extension can sometimes tighten up that joint.
If the LTF does NOT help with shifting, do multiple DipTube HandPumps+FreshMerconV routine described in my prior post above.
If that does NOT help, do full Tranny service: PanDrop + New Filter + New PanGasket (needed anyway) + 5~6qt New MerconV + BandAdjust.
If that does NOT help. a new\rebuilt ValveBody with new TopBondedGasket+Solenoids+ShiftKit... CentralValveBody\Donny in OK is a good source.
If that does NOT help, time to consider a new\rebuilt Tranny.

 

[4X4XFD]

Thanks to everyone for your help and recommendations. The weather is still very much winter here in SW Mo and I have no garage. So I'll wait till the temps are warmer and sunny skies before I do anything. I'll try to keep this thread updated with what I do and the outcome, if it doesn't pass on to obsolete for age. Experience is very valuable and I want to share mine. Thx