Transmission Fluid Change

Brother A

Brother A

Senior Member
I'm about to change my transmission fluid. I haven't done that since I bought the car last year. It may not need to be changed but it leaks past the threads of the drain plug. That makes me suspicious that what's in there is due for a change or the wrong viscosity.

I was reading repro of the Ford "Instruction Manual" for the Model A and it suggested rinsing the transmission with kerosene after draining the fluid. What do you guys think about that? Is it something that was necessary with the fluids of that time or is it still good practice?

Also, I was thinking about using teflon tape on the drain plug just for some insurance. For some reason I recall reading that that may not be a good idea. I couldn't find that thread when I searched. Do any of you recall that?

Thanks for your help.

Steve
 
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I would suggest you use a fairly thick gear oil like Mobil 680 or equivalent (Shell, Chevron and other companies make the same type of thick gear oil). I am not sure you need to use any kerosene to "clean" the gear box. It probably wouldn't hurt anything inside it if is only driven a very short time with kerosene (fuel oil). I am a little suspicious of some of the "600W" oils sold by model A parts place as you really don't know what it really is. I used a little Permatex with Mobil 680 dear oil on the threads of the lower plug and have no leaks (so far). Good luck.
Rusty Nelson
 
Steve,
Your filler plug and drain plug on the trans. are interchangeable so you might want to swap them and check for the leak. Both are NPT threads and tapered. Are you sure it's leaking from the plug or just following the bottom of the trans down from the front? No recommendations about fluid since it opens such a can of worms around here.
Pete
 
My plug on the diff. was also leaking when I bought the car, I found it was loose, Tightened it, no more leak, Try that 1st.
I would not use kerosene to flush it, I did use some left over eng. oil [new] just poured it in trans. and diff. and drained it out to flush what was on the bottom,
Did not drive it.
This is JMO.
 
Thanks guys. I have tightened the plug and checked it a few times with no improvement. It's just weeping and hasn't appreciably changed the oil level in a year. I'm fairly certain it is leaking from the plug but this change will be the test.

I like the idea of swapping the drain and filler plugs. I will also probably go with the black Permatex rather than the Teflon tape on the plug.

I also like the suggestion of using engine oil to flush the ******. I was a concerned that any residual kerosene would just serve to dilute the heavy weight oil. Probably not much but since it so important to have "sticky" oil on those straight cut gears and we are all concerned that the 600W oil we get today may not be what it used to be,I didn't want to do anything to make the matter worse. I liked the idea of flushing the ****** but just not with K.

All good stuff. I don't know what I'd do without the barn!
 
If the original manufacturer (Ford) recommends flushing with kerosene, why question the procedure? Just asking.
 
Henry recomended adding kerosene to the ****** for winter driving.
It certainly can't hurt to run kero through it to clean out any old sludge prior to refilling.
Maybe put some Permatex Number Two on the threads of your drain plug when replacing it? Its impervious to oil and gas.
The 600 W product as obtained from the vendors does an excellent job, even if each might have his own secret blend.
 
I always flush the trans with kerosene when changing the fluid. First, drain the old oil then take the shift tower off the trans and fill it 3/4 full with kerosene and let it sit overnight and use an old tooth brush to swab as much of the insides as possible, then drain it and blow it out with compressed air (hold a large rag or towel over the top) put the plug in and refill with 600W. PS - "Flush" does not mean to fill it and drive it.
 
With the engine running in neutral, clutch engaged, the cluster gear is spinning. That should effectively power wash the inside of the trans. if you put some Kero in it after draining the old oil.
 
J Franklin said:
If the original manufacturer (Ford) recommends flushing with kerosene, why question the procedure? Just asking.
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The org. manufacturer [Ford] also recomened ether drain'ing your rad. at night in the winter or using alcohol as an anti-freeze, I guess you could still do that, But I like the 50/50 of today.

As far as using kerosene for flushing, I don't know if the trans, or diff. build up enough heat to evaperate any traped kerosene which could dilute what ever lube you use. All this is JMHO ;). I have been wrong many times before...Agin JMO.
 
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Ponder these:
1- Most aren't going to change types of gear oil or motor oil, they'll say, "My mind is made up, don't mess with me!"
2- Kerosene cleaning: Henry didn't know the best ways of doing everything way back then and lots of products hadn't been invented. Hank would have loved LOCTITE!
3- A poster once said, "I think I have enough knowledge to last me the rest of my life!"
4- Isn't it great fun how we ALL process info differently, if we all did it the same, there would be no use talking, just GRUNT occasionally so folks would know you're alive!
5- Yes, Ol' Bill is VERY opinionated, and an independent "thinker," a procrastinator, etc, etc, like many out there. Wish we could all get together, eat squirrel & dumplings, nip on MOONSHINE, tell stories, etc. That could be the FUNNEST PARTY OF THE CENTURY!!! On leaving, when stopped for suspected D.U.I, just tell the ocifer that you have loose wheel bearings!!! Bill W.
 
Bill I'm going to be heading out to California in a few days. Not going to be particularly close to you but just being in the same state as you is going to put a grin on my face. Next time I eat squirrel I'll be thinkin of you. No dumplings for me but the moonshine sounds good.
Dave
 
I would not mind flushing the trans with Kero, Diesel, heating oil any light oil based substance except gasoline or USED ENGINE OIL! Few if any, send used oil out for analysis. Yet as a pilot and aircraft owner I would not consider an oil change complete without an analysis. When taking the sample, we would draw when the oil was about halfway drained. Not the beginning, nor at the end of the drain. This was to get a representative sample. The oil analysis would show the metals that were present in the oil. Metals that used to be part of the engine. This is true of the air force also. The difference being that the AF test after every flight. This is where the fallacy of being able to never change your oil falls apart. Yes, the oil doesn't wear out as such, but your crankcase needs to be flushed to get the metals out. These metals act like a fine abrasive and cause your engine to wear out prematurely. And yes, we did use an oil filter on aircraft engines! Don't pour anything in your engine or trans that might leave something behind.
Terry





Brother A said:
Thanks guys. I have tightened the plug and checked it a few times with no improvement. It's just weeping and hasn't appreciably changed the oil level in a year. I'm fairly certain it is leaking from the plug but this change will be the test.

I like the idea of swapping the drain and filler plugs. I will also probably go with the black Permatex rather than the Teflon tape on the plug.

I also like the suggestion of using engine oil to flush the ******. I was a concerned that any residual kerosene would just serve to dilute the heavy weight oil. Probably not much but since it so important to have "sticky" oil on those straight cut gears and we are all concerned that the 600W oil we get today may not be what it used to be,I didn't want to do anything to make the matter worse. I liked the idea of flushing the ****** but just not with K.

All good stuff. I don't know what I'd do without the barn!
Click to expand...
 
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1crosscut said:
Bill I'm going to be heading out to California in a few days. Not going to be particularly close to you but just being in the same state as you is going to put a grin on my face. Next time I eat squirrel I'll be thinkin of you. No dumplings for me but the moonshine sounds good.
Dave
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Dave,
Too bad we couldn't meet, got a great story of my Grandfather designing new crosscut saw & sold the design to Atkins Saw Co. in 1932 for $3,500.00!
That was a bundle in those days. Bill W.
 
I always put small powerful magnets in the pockets of the drain and fill plugs. This will collect any fine metal particles and should help the life of the ****** bearings and gears. It also lets me easily see whats happening as far as wear.
 
Tom Wesenberg said:
I always put small powerful magnets in the pockets of the drain and fill plugs. This will collect any fine metal particles and should help the life of the ****** bearings and gears. It also lets me easily see whats happening as far as wear.
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Tom,
Knowing you, you could wire something up from those magonets to indicate true NORTH, so's you don't get lost.:D If you end up at Carl G's place, you'll have to re-calibrate! Bill W.
 
BILL WILLIAMSON said:
Tom,
Knowing you, you could wire something up from those magonets to indicate true NORTH, so's you don't get lost.:D If you end up at Carl G's place, you'll have to re-calibrate! Bill W.
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That's how I find the north end of the original ammeter magnet, if it's removed from the case. I just hang it from a thread and wait while it turns north. If it's installed backwards, the meter reads discharge when it should read charge.
 
Oh! it's fun to have your ammeter runnin' basackwards, my cohorts really wonder if I got all my cotter keys straight!!
I respond with a pathetic look, and it gets me free coffee.
Bill W.
 
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