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Transmission fluid level check, Manny method. [message #345335]

Mon, 15 July 2019 09:08

RF_Burns

Messages: 2277
Registered: June 2008
Location: S. Ontario, Canada

Karma: 3

Senior Member

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

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Re: Transmission fluid level check, Manny method. [message #345337 is a reply to message #345335]

Mon, 15 July 2019 09:23

Ken Burton

Messages: 10030
Registered: January 2004
Location: Hebron, Indiana

Karma: 10

Senior Member

RF_Burns wrote on Mon, 15 July 2019 09:08

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

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Re: Transmission fluid level check, Manny method. [message #345363 is a reply to message #345335]

Mon, 15 July 2019 17:01

RF_Burns

Messages: 2277
Registered: June 2008
Location: S. Ontario, Canada

Karma: 3

Senior Member

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?

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Re: Transmission fluid level check, Manny method. [message #345366 is a reply to message #345335]

Mon, 15 July 2019 18:05

jhbridges

Messages: 8412
Registered: May 2011
Location: Braselton ga

Karma: -74

Senior Member

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

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Re: Transmission fluid level check, Manny method. [message #345368 is a reply to message #345335]

Mon, 15 July 2019 18:09

RF_Burns

Messages: 2277
Registered: June 2008
Location: S. Ontario, Canada

Karma: 3

Senior Member

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

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Re: Transmission fluid level check, Manny method. [message #345371 is a reply to message #345335]

Mon, 15 July 2019 19:27

JohnL455

Messages: 4447
Registered: October 2006
Location: Woodstock, IL

Karma: 12

Senior Member

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

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Re: Transmission fluid level check, Manny method. [message #345373 is a reply to message #345368]

Mon, 15 July 2019 20:30

Jp Benson

Messages: 649
Registered: October 2011
Location: Fla

Karma: 2

Senior Member

RF_Burns wrote on Mon, 15 July 2019 18:09

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

Exactly the same measurements as mine. For a lot of reasons it's handy not having fender wells. Pull the trans dipstick and measure without opening the hatch for one.

My coach ran for quite a few miles with no sign of trans overflow. I installed an overflow reservoir and it accumulated about half a cup. That hasn't changed for several months.

http://www.gmcmhphotos.com/photos/restoration-photos/p66505-transmission-overflow.html

JP

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Re: Transmission fluid level check, Manny method. [message #345375 is a reply to message #345335]

Mon, 15 July 2019 21:02

RF_Burns

Messages: 2277
Registered: June 2008
Location: S. Ontario, Canada

Karma: 3

Senior Member

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!

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Re: Transmission fluid level check, Manny method. [message #345376 is a reply to message #345375]

Mon, 15 July 2019 21:58

Ken Burton

Messages: 10030
Registered: January 2004
Location: Hebron, Indiana

Karma: 10

Senior Member

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

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Re: Transmission fluid level check, Manny method. [message #345408 is a reply to message #345376]

Tue, 16 July 2019 12:20

rjw

Messages: 697
Registered: September 2005

Karma: 4

Senior Member

Ken Burton wrote on Mon, 15 July 2019 22:58

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

Roller Cam 455, TBI+EBL, 3.42 FD, 4 Bag, Macerator, Lenzi (brakes, vacuum system, front end stuff), Manny Tranny, vacuum step, Tankless + OEM water heaters.

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Re: Transmission fluid level check, Manny method. [message #345445 is a reply to message #345408]

Wed, 17 July 2019 07:30

6cuda6

Messages: 975
Registered: June 2019

Karma: -6

Senior Member

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

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Re: Transmission fluid level check, Manny method. [message #345538 is a reply to message #345335]

Thu, 18 July 2019 22:07

RF_Burns

Messages: 2277
Registered: June 2008
Location: S. Ontario, Canada

Karma: 3

Senior Member

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.

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Re: Transmission fluid level check, Manny method. [message #345545 is a reply to message #345538]

Fri, 19 July 2019 02:50

Ken Burton

Messages: 10030
Registered: January 2004
Location: Hebron, Indiana

Karma: 10

Senior Member

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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