Transmission fluid level check, Manny method.

RF_Burns

RF_Burns

Super Moderator
Staff member
Sep 7, 2008
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Ontario Canada
So I've mentioned before I can't effectively read the tanny dipstick with any accuracy. I've got a bit of fluid coming out the vent so I'm wondering
if the level is a bit high.

I'm going to try the Manny method of removing the modulator and letting the excess drain out the modulator mounting hole... that should be the Full
level.

So
-Take the coach for a drive to get the tranny up to operating temperature.
-park on a level area and run the shifter through all positions.

I'm assuming I shut OFF the engine before removing the modulator?? (Gene's site does not say)

How long do I have to complete this operation before the torque converter starts draining down?

I have a Ragusa tranny pan, I'm guessing that should not matter.

Thanks

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
> So I've mentioned before I can't effectively read the tanny dipstick with any accuracy. I've got a bit of fluid coming out the vent so I'm
> wondering if the level is a bit high.
>
> I'm going to try the Manny method of removing the modulator and letting the excess drain out the modulator mounting hole... that should be the
> Full level.
>
> So
> -Take the coach for a drive to get the tranny up to operating temperature.
> -park on a level area and run the shifter through all positions.
>
> I'm assuming I shut OFF the engine before removing the modulator?? (Gene's site does not say)
>
> How long do I have to complete this operation before the torque converter starts draining down?
>
> I have a Ragusa tranny pan, I'm guessing that should not matter.
>
> Thanks

It is not going to drain that fast. Just pull the modulator with engine off for 15 seconds or until it quits running and then reinstall it. Ragusa
pan makes no difference.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Ok, took the coach out for a run, got the tranny nice and hot (~160F).

I checked the dip stick, level ground, engine running in park and it was not quite 1/2 way between Add and Full.. just about right by the stick. I
noticed there was a few bubbles on the stick.

Then I got everything ready to check via the modulator method underneath. I then started the engine and ran it though the gears then shut it Off and
got down under. Had a clean oil change pan under the tranny to catch the fluid. It came out full stream so I let it go for about 20-30 seconds and
then it was down to about a 1/8" stream coming out. suddenly there was a second rush which I assume was the modulator valve had moved out to the edge
of the tranny case... so I put the modulator back in.

I then went above and check on the stick, engine OFF and it was down to about at the Add level. I then started the engine, put it through the selector
positions and returned to park. With the engine running it appears to be about 3/16" below the add mark.

I measured the amount of fluid that came out as 750millilitres = 0.8US quarts or about 1.6US pints.

After about 10 minutes of the engine not running, the level appears to be about 2" + above the full mark, so the converter drains down pretty fast!
Converter is an Allison new with rebuilt tranny with about 25K miles.

So, my choices:
-Go with dipstick and add back about 1.6 pints of fluid
-Or dipstick is wrong and go by modulator level?

What say yea?

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
I'd go with the dipstick, particularly if you have a quick draining torque converter. My transmission guy sez these won't survive very long even a
quart or so low. I watch the overflow bottle, I'm not getting any juice in it.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
So, in an effort to check whether I have the correct tranny dip-stick, I tye-wrapped the dip stick along the outside of the tube and bent it to follow
along the bend in the tube where it enters the tranny. working alone in many contortions, it appears the Add mark would be at about where the pan
meets the tranny case. According to Gene's site for dipstick calibration, the Full mark should be 1/4" below that point and Add another 1/2" beyond
that. So by that, my dipstick is too short by 3/4" or so.

The measured length of my dipstick from the rim of the cap at the top is 19" to the Full mark and 19.5" to the add mark. Anyone able to measure their
tranny dip-stick to compare?

Thanks

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
Letting it spill out the hole IS NOT THE FULL LEVEL. It's full level recalibration mark on the stick only. Then you have to button it up and run it
in park and ADD fluid to get it up to that NEW mark.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
Thanks all. I'm likely over thinking this... so I'm going to add back new fluid, the same amount I took out today.

I have the GM right angle tube adapter for the vent, I'm just leery about pulling the old vent out and dropping some metal bits down inside!
--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
Bruce, CALL MANNY and listen to his recommendations. You are getting too many conflicting recommendations that I personally do not agree with. The
big thing I have the concern about is the presence of bubbles in the fluid dwhich is some foaming an indicates the anti-foam additive in the fluid is
worn out or you are over full. Can Manny and ask / follow his advice.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
> Bruce, CALL MANNY and listen to his recommendations. You are getting too many conflicting recommendations that I personally do not agree with.
> The big thing I have the concern about is the presence of bubbles in the fluid dwhich is some foaming an indicates the anti-foam additive in the
> fluid is worn out or you are over full. Can Manny and ask / follow his advice.

I will admit that I don't pay much attention to the tranny fluid level. I would love to hear what Manny recommends. I have one of his rebuilds with
over 55,000 miles on it with one fluid change and due for another one.

--
Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com


Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator, Lenzi stuff, Manny Tranny etc.
 
Bruce are you checking you fluid level with trans hot, engine running and in neutral? Sounds like your doing it engine "off", and trans hot (unless
I'm missing something in the post)....

It needs to be checked engine running, trans at operating temp and in neutral or your reading will be wrong.....

The only time you would do it trans cold, engine running is if the dip stick actually says "cold min" "cold max" on it....any other time your Mark's
would be "hot min" and "hot max"
--
Rich Mondor,

Brockville, ON

77 Hughes 2600
 
Ken,
I replaced the fluid that I removed doing the modulator level check thing. So now the fluid is back to the level it has been for the past few years.
I didn't get to call Manny yet since we left for the east coast early Tuesday morning. I'll give him a call tomorrow.. I'm guessing he is 3 hours
behind Eastern Standard Time.

6cuda6, Yes, I check the tranny fluid with the transmission Hot, in Park, engine idling. The trouble I have is trying to read the level accurately.
The dipstick comes out smeared with fluid several inches up the stick. Cleaning it and trying again does not help the issue.

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
This will get you close.

Check it cold.
1. Pull the stick, wipeit clean, and set it aside.
2. Let the coach sit for a few hours to let any fluid in the tube drain down so the stick will not get smeared fluid on it during hte following steps.

3. Start the coach and remove the modulator to let any excess fluid drain.
4. Reinstall the modulator.
5. Insert the stick in the now dry tube.
6. Pull the stick and try to read it by placing the stick against a clean a white paper towel or napkin.

You now know the correct full level as it reads on the stick and the possibility of foaming up the fluid during this process has been minimized.

Once that level has been determined you and later check it again when hot if desired. Usually these two readings will be within 1/2 pint of each
other and this the difference between hot and cold.

Nothing says checking the calibration of the stick by removing the modulator has to be done hot.

Checking of the operational level should be done hot.

I asked you to call Manny so I did not have to be one of many different opinions that you had to sort through and decide which to follow.

Yes Manny is in the Pacific time Zone.


--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
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