Transmission Longevity Tips

[C420sailor]

I’ve noticed a bit of an uptick in transmission posts here lately, and figured I’d start a thread on ‘best practices’ for increasing tranny longevity in these trucks—especially the weaker gearboxes like the 5R55E.

These tips have allowed me to take my transmission to over 340,000 total miles (200,000 since last rebuild), and she is still going strong.

Feel free to add in something that has worked for you.

1. Change your fluid. I’m not sure exactly what the recommended interval is, but fluid is the life blood of your transmission. Unlike engine oil, which is only used for lubrication and cooling, transmission fluid also functions as a hydraulic fluid. This means that it acts on items with seals. As friction material in the trans (torque converter clutch, clutch pack frictions, etc) wear, these particles begin to circulate. Now, pay attention to what I just said—FRICTION MATERIAL. You don’t want this eating away at bores and seals. I change my fluid every 30,000mi, but whatever you do, change it before the color begins to change, and change it regularly with Mercon V ONLY. Install a drain plug in your pan to make it easier. If you rebuild your transmission, see if you can get a torque converter with a drain plug. Stock 5R55E guys can use the cooling line/bucket method.

2. Warmup. I know this is controversial. Many articles have been published saying that warming up a car isn’t necessary (some say it’s harmful), but these articles usually focus solely on the engine cylinders. Remember that a powertrain is more than just a set of reciprocating pistons. In this case, we are using an oil-based fluid to hydraulically actuate parts within the transmission. Cold fluid has a higher viscosity, which will result in higher pressures. Cold fluid means cold seals, and cold seals tend to be harder and more brittle—prone to blowout and/or tearing. Giving the truck even just a few minutes to warm up, especially in cold weather, can raise fluid temperatures enough to be more gentle on your transmission when you put it into gear. Also, the lowered idle RPM of a slightly warm engine will be easier on the transmission when you select a gear. Warmup also helps your power steering system! If you have a block heater, use it! That heat will migrate to the transmission.

3. If you tow, or you live in a very hot climate, consider adding an auxiliary cooler (or a larger aftermarket cooler). Cool (not cold) fluid is happy fluid.

4. Consider installing an external fluid filter. There are various types. Some are magnetic and simply plug into the cooling loop near the cooler. More complicated systems involve bolting a spin-on filter housing to your frame. I made my own version of the latter and it functions very well, as oil filters have much finer media. Make sure you take into account cooling loop flow direction.

5. Periodically change your pan filter. These filters are designed to catch large particles. Most are 80-120 micron filters. Oil filters are in the 10-30 range, for comparison. This doesn’t need to be done every fluid change, but come up with a regular schedule. While you’re in there, clean off your pan magnet and, using a good inch-pound torque wrench, check valve body torque. Make sure you reference the torquing diagram and values in the service manual.

6. Come to a complete stop when changing gears, and allow the new gear to fully engage before stepping on the gas. You’d be surprised how many people don’t do this.

7. Don’t beat on your truck. Don’t drive hard if you don’t need to. Sometimes I need to accelerate hard, but I try to come off the throttle a little in anticipation of the next shift, if I can.

8. Adjust your bands. The R55 boxes have adjustable bands. They don’t need adjustment often, but regular adjustment will make the bands last longer.

9. If you need a rebuild, find a QUALITY shop (if you don’t DIY). The better the warranty, the better the job. Many of the shorter warranty shops will simply replace what is obviously worn (frictions, maybe the torque converter too), gaskets and seals, and hope you make it past the 12-month warranty. Ask them if they rebuild the transmission to current Ford specifications. Ask them what company they use for various parts. Ask them what they replace. Ask questions.

10. Maintain your driveline. Worn CV or u-joints introduce slack, which can cause shock loading during gear selection and driving. That shock will shorten the life of your transmission.

11. If you’re running big tires, seriously consider gearing. Big tires with tall gearing imparts more stress on the transmission.

12. Don’t forget your transfer case! Change the fluid regularly with the appropriate fluid. Mercon V is NOT for use in transfer cases.

13. If you get a flashing OD OFF light, or if you notice funky shifting or trans issues, address it IMMEDIATELY.

14. If you’re towing, or driving up a long, steep grade, consider using the OD OFF button.

What else do you guys have? Let’s hear it!

 

[Flashflood]

I'll add my 2 cents in.
15. In town keep overdrive off this helps with it not locking the trouge converter up on short trips.
16. If you check your valve body make sure to check your connectors and wires. That's how mine went.
17. Almost all ford automatics have there reverse and overdrive bands are connected so if one goes your on bide time.
18. I would recommend not using the cooler technique to change your fluid, you could blow out your pump.
19. Flush the cooler lines ever so often. ( Just the lines not transmission). This will help with junk in the lines.
My 5r55e had 198k on a switched instrument cluster still original tranny

 

[410Fortune]

Add a temp gauge or obd live data so you can monitor the trans fluid temp

Consider aftermarket pan with extended capacity

Heat kills auto transmission fluid

 

[C420sailor]

By ‘cooler method’ I mean letting it pump a 2-3 quarts out and topping off, repeating until 12ish quarts through…not waiting until the pump runs dry and the coolant lines spit air.

As long as you don’t empty the pan, no damage can occur.

 

[dvdswan]

Great information. Thank you for sharing. I have to admit I'm sort of new to the Ford transmission maintenance. In all honesty, I've never had to change trans fluid as I've always had manuals. I have an 02 Explorer XLT for 3 years with 150k now, my new 02 ST has 124k now, and my 91 Ranger for 3 years has 130k now. I've been looking to change the fluid but have been leery because I thought you couldn't lower the pan because there isn't a dipstick to refill. IIRC, you needed some sort of threaded tool that would allow you to fill the pan and would drain the excess back out.

I should note that all the transmissions shift just fine. The AL4D has a very solid shift all the time, like a shift kit was installed.

So, my question would be. What is the best process to change fluid on the 5R55Es and on the AL4D? I haven't verified but I believe both 02s have transmission coolers. Should those be drained and filled as well? I'm also reading there are 5R55W and 5R55S models. How can you tell what model you have?

Is there a YT video that best describes the procedure for this?

 

[410Fortune]

For the a4ld and 5r drop the pan
Change fluid and filter

A4ld I would do every 20-30k miles
And add a second cooler to that trans for sure

For the 02 w no dipstick drop the pan change the fluid and filter
Buy the fill tools it’s not expensive
After that you can do cooler style
Flushes every 30-50k miles

Cheap insurance!!!

I use lubeguard additives in my auto transmissions the stuff is proven to work and is industry standard

 

[C420sailor]

Great information. Thank you for sharing. I have to admit I'm sort of new to the Ford transmission maintenance. In all honesty, I've never had to change trans fluid as I've always had manuals. I have an 02 Explorer XLT for 3 years with 150k now, my new 02 ST has 124k now, and my 91 Ranger for 3 years has 130k now. I've been looking to change the fluid but have been leery because I thought you couldn't lower the pan because there isn't a dipstick to refill. IIRC, you needed some sort of threaded tool that would allow you to fill the pan and would drain the excess back out.

I should note that all the transmissions shift just fine. The AL4D has a very solid shift all the time, like a shift kit was installed.

So, my question would be. What is the best process to change fluid on the 5R55Es and on the AL4D? I haven't verified but I believe both 02s have transmission coolers. Should those be drained and filled as well? I'm also reading there are 5R55W and 5R55S models. How can you tell what model you have?

Is there a YT video that best describes the procedure for this?

Here’s what I do, but mine has a dipstick. You’ll need the tools for yours. This is best accomplished with a friend, but not required.

Park your truck on a level surface. Disconnect the hoses from the transmission cooler, and put them in a graduated bucket. Start the truck, and let it run until you have 2-3 quarts in your bucket. It may take a couple minutes for fluid to start flowing. Shut the truck off. Using the graduated lines on the bucket, add that same amount of fresh fluid via the dipstick tube.

Start the truck again. Another 2-3 qts. See where this is going?

Keep doing this until you have 12-14qts (I use 12 for the 5R55E and 14 for the 4R70W) through it.

Is this as good as a true drain and fill? No. You’re continually diluting the fluid. But once you get on a regular schedule, it’ll keep your fluid fresh and cherry red.

When you do your last fill, reinstall the hoses and verify the amount of fluid in your bucket equals the amount you added, start the truck, and check the level.

 

[dvdswan]

Here’s what I do, but mine has a dipstick. You’ll need the tools for yours. This is best accomplished with a friend, but not required.

Park your truck on a level surface. Disconnect the hoses from the transmission cooler, and put them in a graduated bucket. Start the truck, and let it run until you have 2-3 quarts in your bucket. It may take a couple minutes for fluid to start flowing. Shut the truck off. Using the graduated lines on the bucket, add that same amount of fresh fluid via the dipstick tube.

Start the truck again. Another 2-3 qts. See where this is going?

Keep doing this until you have 12-14qts (I use 12 for the 5R55E and 14 for the 4R70W) through it.

Is this as good as a true drain and fill? No. You’re continually diluting the fluid. But once you get on a regular schedule, it’ll keep your fluid fresh and cherry red.

When you do your last fill, reinstall the hoses and verify the amount of fluid in your bucket equals the amount you added, start the truck, and check the level.

Much appreciated. This is added to the to do lists. Thank you.

 

[410Fortune]

You should change the filter once at least after the cooler flush method is a great time to change the filter because you just flushed a bunch of new fluid through and out with the old

I did the cooler method a time or two on a Ford escape it works fantastic

 

[dvdswan]

Just so I'm clear, you're adding the exact amount of fluid removed. But to check the fluid level properly I will need the tool. Is that correct?

I would be dropping the pan to replace the filter anyway, so I'm going to need the tool regardless.

 

[C420sailor]

I can’t speak to that model. But you need whatever special tools are required in order to add fluid AND check the level.

If you’re scientific about it, and accurate, you should end up with the level at the same place when you’re done. But you still have to check and possibly tweak it

 

[410Fortune]

For the 02 with no dipstick = Exactly

Level is checked with truck on level ground warm and in park.
My wife’s Toyota is similar to this except no tool required you just remove a plug and let the trans Fluid drain out until it stops then you are at level. Tons of fun when Toyota world standard fluid is about $12-15 a quart

 

[newmantjn]

Hi everyone; I spent 35 years in automatic transmission calibration and design. 30 at Ford including stints on 6R and 10R60 Explorer applications. I did not work on the 5R, but with respect to the comments above:
1. Fluid: ANYTHING you can do to keep your fluid fresh, clean and cool is generally beneficial. Friction modifies in the fluid break down with age and heat. Your trans will generally shift better and be better lubricated with fresh fluid. You may avoid thing like TCC shudder if you change your fluids.
2. Warmup. You will probably be happier with the way your transmission behaves if you allow it to warm up. The fluid viscosity gets ridiculously high at very, very low temperatures. Seals shrink and don't "blow out" to the sealing edges of the groove/bore as quickly when cold etc. Pushing viscous fluid through small control orifices is tough. Even the solenoids act different. Bottom line is that the transmission will probably be smoother and you will probably be happier with it once it warms up some. I am not aware of any durability implications of running cold, so ... do what you want.
6. I can't think of any reason why this would matter one way or the other. If you do a rolling stop and leave in 2nd gear or whatever, who cares?
11. I don't think this matters much either. The tractive force required to move a vehicle is a function of speed, rolling resistance, frontal area and coefficient of drag. Big tires probably have higher rolling resistance, but other than that... I don't know. Generally though, these vehicles were designed and tested with the equipment they came with. If you run other stuff, you may run into unintended consequences.
14. If you are experiencing powertrain hunting and pushing OD cancel calms it down, by all means, do it. If you are going downhill and pushing the button keeps you in a lower gear, so you don't have to brake, go for it. If it makes you feel happy, push the button. I don't know that it will help a ton one way or the other though with durability, with the exception of potentially reducing powertrain hunting if you are experiencing it (which, hopefully, you are not).

 

[C420sailor]

By #6 I mean people who will still be rolling back when backing out of a driveway or parking space and slam it in drive without stopping. Often accompanied by immediately stepping in the gas. Come to a complete stop, shift into drive, wait until you feel it settle into that gear, then release the brake and step on the gas.

#11, it’s no different than driving up a hill, or driving with the brakes dragging. Taller gearing, whether via actual gearing or taller tires, places more stress on the driveline upstream of it, all else being equal. Think of a manual—is the clutch going to slip in 1st or 6th?

 

[usapadyra]

Interesting thread. Glad to see I've been doing most the listed tips here almost since getting the truck at 150000 miles.

There are a couple of things I do to manage overdrive shifting (up into and down out of).

I anticipate climbs that I know the car can't maintain in overdrive at 60/65 and disable overdrive at a lower speed. Even better if I can disable overdrive before actually shifting into it and climbing. If I'm driving an unfamiliar road uphill and it catches me unaware, I will slow down to maybe 50/45 and keep the throttle in the low-mid range to minimise the disparity in engine / gear speed. It's kind of like an automatic version of rev matching....not really but I think you will know what I mean. Needless to say I only do this if traffic permits. I sometimes have to accept a shift out of overdrive at 60/65mph if I'm in a pack of traffic. I don't think it's the end of the world, but can't hurt to keep it to a minimum.

The main thing I'm especially trying to avoid is the following:
- cruising at 65
- uphill section
- slowly lose speed as torque is not adequate in overdrive
- compensate by pushing throttle further and further
- still losing speed
- combination of throttle position and lower speed force a downshift at hard throttle

Maybe it's the age of the car, but the way the shifting is mapped in this particular scenario feels a touch dimwitted and I can't help but feel like it leads to unnecessary wear and tear.

Forgot to add - I believe it's good practise to try and maintain speed by modulating the throttle, rather than coming entirely off and getting back on repeatedly. I've noticed the overwhelming majority of people I know (plus taxis) drive like this. On off on off on off etc, rather than just backing off a little and holding it there. My understanding is that this leads to accelerated wear since the TCC will be actuating way more often than it needs to, and there is slippage whenever a gear has to re-engage thus reducing the lifespan of friction materials. Please correct me if I'm wrong about this.

Either way, it reduces the wear and tear on driveline components since you aren't constantly reversing the direction of drive.

 

[C420sailor]

I drive the exact same way. I do my best to avoid that hard OD downshift, and I also play the ‘try to keep the TCC locked’ game on the interstate. Cruise control works well for this in stead state, but if you ask it to decel even 1mph, it’ll pull so much throttle that an unlock is guaranteed. I can usually ever so slowly bring the speed down and gently catch it, not forcing an unlock.

I read some advice on here years ago. It was for fuel mileage, but also applies to longevity: drive like you have an egg between your foot and the pedal.

 

[410Fortune]

The 5.0 awd trucks seem to take forever to downshift trying to get a passing gear or accelerate into highway can have you wanting the shift to come sooner. Exaggerated with larger tires

Mash the skinny pedal and nothing happens.. keep mashing, eventually she shifts. It feels like something was missed at the factory. But then you get used to it.
After all these are only 4 speed autos

The fix? Some tuning can change the 4-3 downshift and the 3-2 also accumulator
Springs and valve body mods can help. Changing from 3.73 to 4.1 diffs also helps a great deal

I’m sure it does not help that I drove these things all over Colorado between 5280 and 11000 ft elevation
Now living in Idaho at 1500’ the power is waaaaay better

 

[sehaare]

I've been doing my own transmission flush since I bought the 98 XLT New.. Before car forums even became a thing (i had a 94 before the 98) there was Dr. Bob with explorer tips. They found their way onto "jeff singleton's maintenance page" and that page eventually made it here. I've used a combination of the methods on that to do my own flush. Not hard to do but don't walk away while doing it.

Changing ATF Ford Explorer Transmission Fluid Change

 

[C420sailor]

I never noticed the 5.0 AWD downshift issue. It seems to tolerate a liiiiittle more “lugging” in OD, but it works with the torque of the 5.0. That said, I run stock wheels and tires.