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FMX oil level

limeyboy

limeyboy

Active Member
Ever since I got my 70 Mach 1 I've found it impossible to get the oil level right according to the dipstick.
I know other people have had problems reading the sticks as well so thought if I post some pics someone can say "that doesn't look right" or " they are all like that".
It has always showed maybe 1/2" over full when dipped ( engine hot, running in P after cycling through the gears) I have tried draining fluid until the point it slips a bit and I have to put fluid back in again, I checked the numbers off of the stick and it seems to be the correct one but is it in the right "position" inside the box? ( too low?)
The top of the dipstick tube is below the bottom of the valve cover, should it be higher which would lift the stick and give me a "lower" fluid level?
The picture of the box shows where the stick sits in the box and if the fluid should be somewhere near the "pan / body" joint I think the stick sits too low.

Anyone any thoughts? the box works great normally ( its a bit noisy in 1st and 2nd ( whirring, not nasty noises) but changes to 3rd by 25mph unless you floor it)

Thanks again for the help I get as if you think it's hard to get FMX info in the US you want to try in the UK ( perhaps Bruno is an FMX guru ???)

Jeff20210521_100333.jpgIMG_20220124_153924.jpgIMG_20220124_153944.jpg
 
Not a guru at all !!
Regarding the dipstick : Thats a difficult one. How do you know you have the correct one ??
I would look for the amount of oil that is prescribed for that transmission .
There should be info of how much oil goes into the carter when only changing the filter ????
If you know that , drain the carter and refill it with that amount .
And then I would adjust the dipstick max index to that level ??? (after running through the gears )
A quick research tells me about 4-5 quarts (4-5ltrs)
Hopes this can be of any help.
 
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When I changed the filter I put a drain plug into the pan to make it easy to change the level.
I put back in less than I drained out which was also less than the book said and the dipstick still showed well over the F mark.
The part number on the dipstick matched up to an FMX one when I checked unless there are different ones for different FMX cars?
I'm hoping someone with a 70 mach 1 can tell me that the dipstick position ( nearly level with the bottom of the valve cover) is correct or low.
I don't know what you would pay for a 351c bare block over there Bruno but there is one over here for 720 euros!! it is the only one I can find for sale here.
 
If the dipstick itself matches the fmx trans by partnumber , maybe you have to check the dipstick tube ???
How much liters a filter change requires depends on the seize of the carter.
I presume a truck has a larger carter and thereby more liters with a oil change.
BTW Do you have a trans oil cooler ??
 
Yes there is a trans cooler, I'll try and measure how much tube there is from the box to the top, does the tube just "push into" the box and seal with the O ring with the bracket to position it?
As the car is such a Heinz 57 as far as the engine goes it would not surprise me if the box came from something else!
 
Thanks for the photo, it looks like your tube is longer inside the box but the dipstick itself might be the same length as mine.
I need to pull the tube out and measure it.
Changed the "new diff" oil yesterday as I've done over 500 miles on it now and there were no big lumps in it thank god just a little bit of a "sheen".
I have realised these cars are VERY tail happy when the road is at all damp so it's been a very calm running in time.
 
Yes , my tube is longer LOL !
And yes , with a trac loc , the rear tends to wiggle !!!
So , premium tires are a must !!!!
 
1969 351W FMX. My tube seems to go in as far as yours does.
 

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You see that hole on the side of your tube ?
I think that hole is there so the air isn't trapped in the tube and prevend the oil to level in the tube ??
Could that be right ?
In that case , the max level should be below or around that hole ??
 
When you enlarge pic "fmx5 " there is a change you can calculate where the max oil level should be ??
 

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I do not believe the top of the filler tube is sealed when the stick goes in to hole, so hole or no hole the level of fluid in the transmission will be the same as in the tube.
 
69GT350H said:
I do not believe the top of the filler tube is sealed when the stick goes in to hole, so hole or no hole the level of fluid in the transmission will be the same as in the tube.
Click to expand...
Yes, you are right. I was in a Mercedes-Benz mind set. Cause on a MB , the dipstick to tube is sealed at the upper side.

Verstuurd vanaf mijn SM-A605FN met Tapatalk
 
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Thanks for all the pics and ideas guy's, here's a thought on Bruno's lines, if the "Full" mark is normally "inside the tube" when you check the level could it be that mine if mine is "in the open" is it "being splashed by fluid moving around in the box" as I try and check it ?
Is the fluid more stable inside the tube?
I'm a bit busy at the moment putting sound deadener on the floor pan and my back aches!
 
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