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Discussion Starter #1
Ok, so i finally got back over to the garage where the 69 was, moved it to my place here a few miles for a few days, then going back to garage. But when i was leaving i noticed a fair amount of transmission fluid (red) under car. A few drops of oil too, but that was less concerning.

This transmission was supposedly rebuilt a decade ago and has about 1000 miles or so on rebuild. This is all unverified.

Anyway, before I drive it back I would like to check this, and wondering if someone can lead me where and how to check this on a 69 mach 1 with I believe an fmx auto trans.

Someone told me I should be able to check it from back of engine bay and add fluid if need be.

I dont have my jack stands and my garage to work in yet. So hopefully th8s is something I can do without climbing underneath. I dont need to fix it this moment, but need to check and add so I can drive without destroying the trans.

Thank you all for the help. I am new to 69s.
 

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You will need to get underneath to fix unless you are luck enough to find it leaking where the dipstick/filler tube enters the trans. It presses in. Another place to check (and easiest to fix) is the lower pan. Tightening the cap screws, a little at a time, working your way around should help if it is leaking at the gasket. Don't overtighten.The pan can also be removed and the gasket replaced. No drain plug here, so it could be a messy process. If the pan is not lthe source, check the small side covers. If the leak is at the u-joint or by the engine, the trans probably will need to be removed. In any case, this should be a straight-forward job for a transission shop. Find a shop that has been around for a long time and they will be very familiar with this transmission. Word of caution: auto trans leaks are deceptive, as the fluid creeps around and fakes you out.
 

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Are you sure it's the tranny? I'd bet it's power steering (if your car is so equipped). Same fluid. Park the car overnight and slide a sheet of cardboard under it large enough to get it under the tranny all the way to the front of the engine. Check where the drips on the cardboard are in the morning. You'll get a better idea of where exactly it's leaking.
 

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Discussion Starter #4
Well that is what i did, and the leak was coming from behind the engine bay where transmission is. I woll do again and check.

Where is the dipstick to check the level? I know it is supposed to be done while it is running correct?

If i need to add fluid so I can drive it somewhere is the place to add where the dipstick is?

Also what kind of fluid is used for these?

Thanks for the help guys.
 

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Discussion Starter #5
In the morning, I will move it to flat ground and try to check.

I will also place more cardboard under and determine where it is coming from.
 

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The dipstick will be passenger-side right by the firewall. It's in a tube that connects to the front of the tranny. Engine should be running and at normal running temp (190-215). The fluid expands so if it's cold it'll read low.
The tube might need to be re-sealed. Alkraut mentioned that.
 

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Get the funnel with a long neck and small bottom that will fit the dipstic tube. They have them at Advance Auto. Pour a little at a time and check level as described above.
 

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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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No way around it, you're going to have to get up under the car. Transmission fluid is a problematic leak. It's very thin and so spreads easily all over the place. The airflow from just driving on the freeway is enough to spread fluid from a leak all the way back to the rear bumper. This makes narrowing down the origin point difficult. Mostly it always looks like the pan is leaking because that's where the drips form. Even if the fluid is coming from further uphill like the dipstick tube seal, the vent, shifter shaft, etc. Transmission shop method is to clean and dry EVERYTHING even close to the affected area. Then drive it a little, let it sit, or whatever makes it leak just little and then look for the leak source.

The original specified fluid is "Type F" because of the design of the original frictions. But since it has been rebuilt and such frictions haven't existed in over 40 years you can use Dexron II/Mercon. Some folks refuse to believe that and insist on using F just like the 55 year old manual says too. Which is OK. Many folks who like a slightly firmer shift will add just one quart of F and fill the rest with Dexron/Mercon. The Chevy folks learned that trick back in the 1970's.
 

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You can check and add fluid to your FMX without needing a jack. The dipstick might say "check when hot & idling in park", so do that. The power steering uses the same exact red fluid as the transmission and parts of the power steering that are very near the transmission often leak. Power steering leaks can be large. An automatic transmission low on fluid may slip a bit when first put into gear. The power steering will make noise if low. Leaks should be fixed, of course, but the car shouldn't be driven without adequate fluids. After a decade, any transmission that has only been driven 100 miles a year is lucky not to leak. Same with the power steering.

You should invest $25 in a Haynes Manual. The basics are well covered in the Manual.
 

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I would first drive the car and get it to operating temperature then shut it off. put it up on jackstands and or ramps or both, degrease transmission bell housing rear main area.. Dry it manually let it air dry or use a blowgun..

Then wearing a respirator because you don’t want this stuff getting in your lungs as it’s dangerous to inhale, get one of those bottles of Johnson’s baby powder and baby powder the entire area. My mornings next light you should be able to go under there and trace where the leak could be coming from
 

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Discussion Starter #11
So turns out i actually had a copy of that manual I dug out of a box I thought was gone. Found section and read about trans check.

So here is my question. As others here have indicated, and the manual said, you are supposed to warm up the engine. The manual said to drive approx 5 miles. Well if i am unsure if this has enough trans fluid, why would i drive it more before i check? That seems counterintuitive.

So tomorrow I am going to go check, but can i just let the car idle to warm up? Is that sufficient?

What should be done if the car needs to be driven to warm up? I dont know how much total it has leaked but in the past 2 weeks it looked significant.

Thanks guys.
 

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Discussion Starter #12
One other quick question, or two.

I got the post about trans fluid and what I can use, but I assume using type F is still fine if I have it readily available? Also is there a difference between brands or would it really not matter?

Type F would be same fluid used in power steering as well?

Thanks.
 

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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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Yes, it's fine. Ford specified Type F for use in almost all their power steering setups until around 1996.
You can check the fluid when cold, sort of. You just need to be aware that it will appear to be low on the stick. ATF expands a LOT as it heats up. Car manufacturers want to see the fluid at a certain level when it is hot and at normal operating temperature. So the stick is marked accordingly. Some newer and other brand cars have sticks that are marked "hot" and "cold". There are even some that are marked according to the actual temperature. All that being as it may, it's still not really a precision measurement. If the fluid appears to be in the ballpark when warmed up we call it good.
 

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I have heard a couple of explanations, both of which involve the transmission vent tube. The FMX can leak out of the vent tube if the car sits long enough for the fluid to drain back out of the torque converter resulting in an over-fill situation. I don't recall the particulars but I think there is a seal for the torque converter which fails in some fashion. Short of a tear down, I seem to remember reading that splicing in an external one way valve in one of the trans cooler lines can be an effective fix for that problem. The other explanation is that same vent tube is plugged up and prevents the transmission from "breathing" which results in high pressure inside the trans causing fluid to be pushed out past one or more of the gaskets or seals on the transmission case.
 

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Discussion Starter #15
Ok, so at cold check, ironically it looked overfull. But it may have been fhe alight slant it was parked on. Anyway pullwd thw cardboard under it for past 2 days, no drips. Well 1 drop of oil.

I check oil, almost seems overfull, checked power steerting cold just to see, and had fluid.

Decided to drive it back to where it is being stored for a couple more weeks. Drove fine, got back and left engine running and checked hot. Power steering was fine. And transmission seemed almost good. It may have been a tick low, but it didnt seem like much.

This is the coldest day we have had in many months, this morning being in the mid to upper 30s. So I didnt know if engine is totally warmed up either.

My plam os, if it seems safe to some thd the experts on here, is to leave it until my garage floor is finished, hopefully a couple weeks. Then bring it back over and I can get more in depth with testing and checking. But if there is some in there I want to do one more test on a slightly warmer day. But if it isnt anything major I want to just fill and top off as needed and when I get into some more major stuff, see if I can get it figured out.

Also, since it didnt get driven more than a few hudred miles a year for the last 12 yrs or so, I want ti see if using it almost "seals" the leaks back up by itself. Maybe rehydrating gaskets or whatever. Maybe a long shot.

Thank you all for the help and I will keep an eye on this. May habe more questions going forward.
 

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Ok, so at cold check, ironically it looked overfull. But it may have been fhe alight slant it was parked on. Anyway pullwd thw cardboard under it for past 2 days, no drips. Well 1 drop of oil.

I check oil, almost seems overfull, checked power steerting cold just to see, and had fluid.

Decided to drive it back to where it is being stored for a couple more weeks. Drove fine, got back and left engine running and checked hot. Power steering was fine. And transmission seemed almost good. It may have been a tick low, but it didnt seem like much.

This is the coldest day we have had in many months, this morning being in the mid to upper 30s. So I didnt know if engine is totally warmed up either.

My plam os, if it seems safe to some thd the experts on here, is to leave it until my garage floor is finished, hopefully a couple weeks. Then bring it back over and I can get more in depth with testing and checking. But if there is some in there I want to do one more test on a slightly warmer day. But if it isnt anything major I want to just fill and top off as needed and when I get into some more major stuff, see if I can get it figured out.

Also, since it didnt get driven more than a few hudred miles a year for the last 12 yrs or so, I want ti see if using it almost "seals" the leaks back up by itself. Maybe rehydrating gaskets or whatever. Maybe a long shot.

Thank you all for the help and I will keep an eye on this. May habe more questions going forward.
When you check it cold:
Start the car, move the snifter to reverse. give it a bit o time. Move it to drive. Pause again. Then put it back in park and check the fluid. If the torque converter is leaking down when parked you want to give the pump the opportunity to fill the converter again. The converter leaking down may also explain your over full condition.

sounds like you have a more involved problem than just a leaky dip stick tube. Likely from sitting too long. I can identify with this problem.
 

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Discussion Starter #17
I wasnt going to check it cold again. I was more going to drive it a few miles, and check it hot and add if need be, then watch and see how much dripping occurs once it is showing as full after warming up engine.

Should i still do the same thing before I start driving or will once i start driving, it will fill the torque converter back up?

Thanks.
 

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If the car moves normally without any pause when you shift into drive and release the brake then the converter is probably fine. Low fluid is also a common cause of a delay after the car has been parked awhile. Transmission fluid expands when it gets heated so you expect the level to be slightly higher when hot. The fluid behaves the same way in a power steering system. Basically you want to check these fluids at their normal operating temperature which occurs a few miles after the engine coolant reaches its normal temperature.
 

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My 69 Mach 1 351 4V with FMX was constantly leaking. After multiple attempts to fix the leaks myself, I took it to a reputable trans shop here in town. They fixed the leaks at the pan and the shifter shaft. I hate to pay someone to work on my car but I hate laying on my back trying to work on a transmission even more. Problem solved. Been dry for a long time now
 

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Discussion Starter #20
Gonna be making a run to walmart prob today. Wanted to check and see if the different brand of type F fluids matter?

Walmart has type F in stock "super tech", which is prob their branded one. Is that sufficient or are other brands "better"?

Thanks.
 
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