An interesting test regarding transmission fluid level readings measured at different ambient temps

[TJC]

I am gratified that you found the info useful.

It is really easy to over fill transmission.

When I measure I always look at the numeric side of the dip stick. It seems to read a tad lower for whatever reason.... maybe fluid flow??. Or picking up fluid in the dipstick tube ... I dunno.

I also wait a few minutes after adjusting the fill to allow the fluid to drain completely into the pan

I keep a 12 pack case of fluid on hand now. My transmission has been trouble free now for going on 10K miles.

I still don't like the way it downshifts all the way down the gears when coming to stop. I know that this is normal behavior, but I rather it behave like my 4G and simply coast to a stop. Will or can a tune correct this behavior?

Sponsored

 

[RedlandRanger]

I probably spent an hour getting the level correct. I tried various methods to see the level on the stick and the one that seemed to work the best was a UV light held at just the right angle - part of the problem is that fluid in the tube can get on the stick and messes up where you see the line. I tried a white piece of Kleenex too but that didn't work too well for me.

When I was pouring in the new fluid it looked darker than I remembered but once it is in, it is still very light on the dipstick - I don't think it is any darker red than it used to be.

One question I haven't seen and I really don't know the answer - how much fluid does it take to raise/lower the level by one number? I know it isn't much - 8oz?

I really like the 5quart jugs of fluid you can get now. The other bonus is I got to use my awesome FitzFunnel too! It worked really slick!

I have a Livernois tune but mine does come down thru the gears when coming to a stop but I really don't feel it too much. For me, the big one I'm wondering if it will change is sometimes I have a weird shift into 8th gear - it is usually at light throttle but it is very inconsistent. Sometimes it is smooth as butter and sometimes it just kind of clunks into gear - its very weird. I tried lubing up the driveshaft spline and it didn't change that behavior at all so I'm guessing it is the transmission.

For those that haven't seen it (I haven't seen it posted here but maybe I missed it), here is an interesting video from the guy from nextgendiesel:



It is hard to know how much of what he says is marketing and how much is true - he certainly sounds genuine. But man, 10 grand for a new transmission? And $3500 for a new valve body?

 

[brroberts]

This is incredibly helpful!

 

[Stevedbvik1]

I probably spent an hour getting the level correct. I tried various methods to see the level on the stick and the one that seemed to work the best was a UV light held at just the right angle - part of the problem is that fluid in the tube can get on the stick and messes up where you see the line. I tried a white piece of Kleenex too but that didn't work too well for me.

When I was pouring in the new fluid it looked darker than I remembered but once it is in, it is still very light on the dipstick - I don't think it is any darker red than it used to be.

One question I haven't seen and I really don't know the answer - how much fluid does it take to raise/lower the level by one number? I know it isn't much - 8oz?

I really like the 5quart jugs of fluid you can get now. The other bonus is I got to use my awesome FitzFunnel too! It worked really slick!

I have a Livernois tune but mine does come down thru the gears when coming to a stop but I really don't feel it too much. For me, the big one I'm wondering if it will change is sometimes I have a weird shift into 8th gear - it is usually at light throttle but it is very inconsistent. Sometimes it is smooth as butter and sometimes it just kind of clunks into gear - its very weird. I tried lubing up the driveshaft spline and it didn't change that behavior at all so I'm guessing it is the transmission.

For those that haven't seen it (I haven't seen it posted here but maybe I missed it), here is an interesting video from the guy from nextgendiesel:



It is hard to know how much of what he says is marketing and how much is true - he certainly sounds genuine. But man, 10 grand for a new transmission? And $3500 for a new valve body?

If you have a 4x4 the new updated 10R80 from Ford is under $3000.00.

 

[RedlandRanger]

If you have a 4x4 the new updated 10R80 from Ford is under $3000.00.

I know, which makes the 10 grand for the nextgendiesel unit even more crazy.

 

[HeatXfer]

For those that haven't seen it (I haven't seen it posted here but maybe I missed it), here is an interesting video from the guy from nextgendiesel:

That video originally posted in this thread:

https://www.ranger5g.com/forum/thre...mission-next-gen-drivetrain.35840/post-776300

 

[TJC]

I probably spent an hour getting the level correct. I tried various methods to see the level on the stick and the one that seemed to work the best was a UV light held at just the right angle - part of the problem is that fluid in the tube can get on the stick and messes up where you see the line. I tried a white piece of Kleenex too but that didn't work too well for me.

When I was pouring in the new fluid it looked darker than I remembered but once it is in, it is still very light on the dipstick - I don't think it is any darker red than it used to be.

One question I haven't seen and I really don't know the answer - how much fluid does it take to raise/lower the level by one number? I know it isn't much - 8oz?

I really like the 5quart jugs of fluid you can get now. The other bonus is I got to use my awesome FitzFunnel too! It worked really slick!

I have a Livernois tune but mine does come down thru the gears when coming to a stop but I really don't feel it too much. For me, the big one I'm wondering if it will change is sometimes I have a weird shift into 8th gear - it is usually at light throttle but it is very inconsistent. Sometimes it is smooth as butter and sometimes it just kind of clunks into gear - its very weird. I tried lubing up the driveshaft spline and it didn't change that behavior at all so I'm guessing it is the transmission.

For those that haven't seen it (I haven't seen it posted here but maybe I missed it), here is an interesting video from the guy from nextgendiesel:

It is hard to know how much of what he says is marketing and how much is true - he certainly sounds genuine. But man, 10 grand for a new transmission? And $3500 for a new valve body?

That funnel is great!

The colder the fluid the easier it is to see. If I check the fluid when I first start it and run through the gears It is about 3/16" up the dip stick and can easily be seen. As the fluid warms and thins out it becomes increasingly translucent.

I have the #4 original dipstick and a new one (thanks Fitz). The older one has thicker lettering and I can see the contrast better on it than the newer version.

I also drilled a hole in the older one in the center of the diamond between 4 and 5. When that hole holds a film of transmission fluid I know the level is correct at 210F. As the fluid temps dropped from 220F I measured at 215F (the top of the Ford window), and then at 10F increments down to 190F. I let the truck sit overnight, and took the lower temp measurements as the temps went from 77.4F (the ambient temp of the cold fluid) up to 180F in 10F increments, while also measuring and recording the time it took to reach each temperature milestone.

A word of caution here if you attempt to drill a hole in the dipstick. The steel is hard, and the drill bit will wonder if you are not very very careful. Using a spring loaded punch I even dimpled the target location enough to catch the bit, and it still tried to wonder. If you at not extremely careful you'll ruin your shiny new dipstick. I used my drill press and clamped the dipstick in place, and the bit (very small diameter) would tend to flex when I applied pressure. A lot of patience and care is required to be successful. I like having that hole at the fill level, but I would advise against it unless you are very proficient, otherwise you may find yourself a repeat MBS customer!

Re: Downshifts when stopping
If I come to a fast complete stop my transmission will lag just a tad as I come to that stop before releasing that last gear. If I glide into that stop, I do not notice it all all... smooth as silk.

I think Ford programmed the transmission to do this as part of the EPA regenerating charge algorithm of the ASS battery effort that gave Ford additional gas mileage points that could not be measured with the existing EPA standards. Barking and coming to a stop is exactly when the battery is overcharged. The engineers wanted to keep the engine RPMs up and use engine braking to overcharge the battery. That's my theory anyway.... and I want to turn it off. Less wear and tear on the drive train, and better gas mileage to boot.

Re: One question I haven't seen and I really don't know the answer - how much fluid does it take to raise/lower the level by one number? I know it isn't much - 8oz?
I didn't explicitly measure, but I know that you will see a substantial difference with 16oz, and I also think you will be able to see the 8oz difference.

RE: Other Thoughts
I tried the UV light and it didn't help me see the fluid any easier... but I have old eyes. Regarding your shift to 8th... Did you add a bottle of LubeGard Platinum to the mix? It does indeed work, at least for me. It will free up your solenoids. Mine were sticking so badly that I could hear them transitioning from inside the cab at slow speeds. It would take ~5 seconds to shift, esp 4-6. All gone now. I know only feel the lower gears shift when under a load.

I know that there is increased wear in my transmission from the early damage. There was a light dusting all over the transmission filter housing and plenty of sludge on the magnet, though no sparkles or chunks. Simply clutch wear.

Thanks for the info on the Livernois tune.

 

[Fitzmotor]

Re: One question I haven't seen and I really don't know the answer - how much fluid does it take to raise/lower the level by one number? I know it isn't much - 8oz?
I didn't explicitly measure, but I know that you will see a substantial difference with 16oz, and I also think you will be able to see the 8oz difference.

I have actually tried to gauge this, but how I was doing it was not really working, what I came up with was hard to get exact, I figured that with the changing volume in the pan due the valve body shape, it made every number a different volume, or I was goofing it up.

And at the time I fiddled with it, it was hot and I was adding cold fluid, and I didn't have the perfect sealing funnel then and lost a little fluid, so then I gustimated the amount and ended up with a different amount per number, so basically, I never got a good test out of it, just a bunch of different sharpie marks on a quart bottle and only the 4-5 and 5-6 were close.

Plus pouring it down cold and checking for every notch is tough, you need to let it sit for the fluid to run down the hose wall, so I wanted to go into the 1/8th pipe hole in my Mishimoto pan with a petcock or a valve and let it out from below cold, so the dipstick can get clean reading.

It's still on my list of stuff to do, because otherwise it's the old "add until full" which is okay but it would be good info to know exactly how much per notch.

So, maybe this post will get me to get it done and get an exact set of numbers!!

Hey Tony, you have done a incredible amount of work in this post, really good info.

 

[Blue Streak]

Tony thanks for a boatload of info & Mike for the Fitzstick. Now if I have all this info correct, some of us do not have the ability to read temp, that is why your info is so helpful, when I check my level cold start as you say & It is just barely on the tip of the stick (which it is) I am to assume I have the proper fill. So for me pumping out old fluid & measuring & installing same amount should put me at normal full level. I am so glad you came up with the cold level check.

 

[TJC]

Tony thanks for a boatload of info & Mike for the Fitzstick. Now if I have all this info correct, some of us do not have the ability to read temp, that is why your info is so helpful, when I check my level cold start as you say & It is just barely on the tip of the stick (which it is) I am to assume I have the proper fill. So for me pumping out old fluid & measuring & installing same amount should put me at normal full level. I am so glad you came up with the cold level check.

This exactly what I have measured. This (and all timed measurements) were taken the following day after was after I validated my fluid level at 215F to be at the middle of the diamond between 4 & 5. This is midway point of the fluid level range window and the top of the temperature window 206F-215F.

Remember to start on level ground, start the engine, run it through the gears (5 second intervals from park to sport mode and back to park) to get the fluid up into the transmission, and then check it quickly... as the fluid expands rapidly when heated. In 11:30 minutes from the time you started your truck, your fluid level should be at the middle of the 1st diamond on the dipstick. At the 17:50 mark your level should be at the 6 on the dip stick. At the 37:20 mark you should be at the 5 mark. You are good if your fluid level is between the hash marks located above or below 5. The entire timed process was performed with the engine idling in park.

You really do need to wait a few minutes when adding fluid to allow it to drain completely into the pan.

You can test the fluid level even further by simply letting the engine run in park while the fluid heat up. At the time intervals I outlined your fluid should be very close to the marks. At idle my fluid stabilized in the 180F to 190F range... at the 37:20 mark I hit 180F.

As I stated earlier, every measurement above 180F (190F - 220F) was measured on the way down (after reaching 225F) on my first pass the day before. Once I had the correct fluid level at 215F, I checked the fluid levels the following day using a stop watch noting the times at 10F degree increments starting at 120F.

One last thought - the AC was on (who knows if it matters).

It would be nice for others to validate my findings.

I am patiently waiting for hot summer temps to see ambient differences. I do not think I will see a large variance, but I am going to test to validate. I've parked the truck in an uninsulated work garage that heats up quite a bit in the July - August dog days of summer here in NC.

Finally, my explanation makes sense to me, but may not to you. Feel free to ask any question and or validate / refute my findings.

Hope this helps.

Edited for Clarity

 

[RedlandRanger]

I drove my truck for a while yesterday and it seems like it is shifting better. It wasn't bad before, but I did have some strange shifts at times. I didn't feel any strange behavior yesterday. It could all be in my imagination (including any potential issues), but fluid changes are never a bad thing. Now that I have the FitzStick and PPE pan, future fluid swaps will be really easy.

Hoping to keep things running well long term - I'm not planning on getting rid of this truck anytime soon.

 

[Kemo Sabe]

So this morning I began taking ambient temps from inside the truck by simply turning the ignition on and recording the temp from inside the cab, them checking then checking the transmission fluid level. Here are my first two entries. The truck has not been started or moved. A 6F change in ambient temperature moved the fluid level up 1/2 a block on the dip stick. A bigger jump than I anticipated.

It reached a high of 66F today, but my garage remains colder longer. I'll keep updating this chart at spring progresses to quantify how ambient temps affect fluid level measurements.

It would be interesting if others could confirm my findings.

UPDATE: 4 May 2025
I am convinced that the rise in fluid levels is due to fluid draining from the transmission over time. I recently let my truck sit for 24 hours and removed 5 qts, Waited 24 hours and pulled another qt, repeated the process again and got another qt. The dropped the pan where another 0.5 qt was in the pan. Removing the filter resulted in more fluid.

Thanks for all your research. Interesting!

 

[TerryW]

If you want to check your transmission fluid level at high temps using the stock dip stick, these pliers are invaluable: https://www.harborfreight.com/11-in-45-bent-nose-long-reach-pliers-64088.html

Sponsored