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Recently bought a used '05 Chevy 2500hd duramax with an Allison 5 speed. I checked the dipstick 3 times cold. Same reading every time. Up past the hot mark. Any reason why there would be excess fluid in the transmission from the previous owner? Does it help when towing at all? It's kinda of a long distance between the hot and cold marks. Should I try to drain some of that? How much fluid does the dipstick dip into, or how much fluid is it from the top of the hot mark to the top of the cold mark?
 

LHN...We ARE the Joneses
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Overfilled.....can lead to running hot conditions when towing in hot weather.
Not a critical thing at this moment.

Since the Vehicle is new to you, might want to consider changing all of the fluids, to establish your own baseline for future maintenance.

Draining and dropping the pan, results in 'bout 2 gallons (7.5-8qts) to refill to the proper level.
 

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Is there a reason for running the fluid level that low? Would it also apply to the later 6 speed?
With a deep pan, the filter moves down and so does the amount it's submerged.

If you go back through all the threads of a Allison overheating, being overfilled is the #1 reason.

Being overfilled by 2% seems to be much worse than underfilled by 5%.

In my race cars, I always ran them a quart low too, for less windage.

Running the Allison (w/ the deep pan) halfway between the COLD and HOT lines at full temp seems to be a good compromise to me. No danger of being overfilled and still having plenty of fluid submerging the filter.

Most folks say their LML runs about 100 degrees above ambient temp.

Mine runs about 75 degrees above. ( About 145 degrees on my CTSII readout on a normal day)

It works well for me.

Yea, My LLY 5 speed and LML 6 speed are both run this way.
 

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Cold Check Procedure
The purpose of the cold check is to
determine if the transmission has
enough fluid to be operated safely
until a hot check can be made. The
fluid level rises as fluid temperature
increases. DO NOT fill above the
COLD band if the transmission fluid
is below normal operating
temperatures.
1. Pull out the dipstick and wipe it
with a clean rag or paper towel.
The transmission dipstick is
located near the center of the
engine compartment. See
Engine Compartment Overview
on page 10-3 for location.
2. Push it back in all the way, wait
three seconds, and then pull it
back out again.
3. Check the fluid level reading.
Repeat the check procedure to
verify the reading.
4. If the fluid level is within the
COLD band, the transmission
may be operated until the fluid is
hot enough to perform a hot
check. If the fluid level is not
within the COLD band, add or
drain fluid as necessary to bring
the level into the middle of the
COLD band.
5. Perform a hot check at the first
opportunity after the normal
operating temperature of 71掳C
(160掳F) to 93掳C (200掳F) is
reached.
6. If the fluid level is in the
acceptable range, push the
dipstick back in all the way.
Hot Check Procedure
The fluid must be hot to ensure an
accurate check. The fluid level rises
as temperature increases.
1. Operate the transmission in D
(Drive) until the normal operating
temperature of 71掳C (160掳F) to
93掳C (200掳F) is reached.
2. Pull out the dipstick and wipe it
with a clean rag or paper towel.
3. Push it back in all the way, wait
three seconds and then pull it
back out again. Repeat the
check procedure to verify the
reading.
4. Safe operating level is within the
HOT band on the dipstick. The
width of the HOT band
represents approximately 1.0 L
(1.06 qt) of fluid at normal
operating temperature.
5. If the fluid level is not within the
HOT band, add or drain fluid as
necessary to bring the fluid level
to within the HOT band.
6. If the fluid level is in the
acceptable range, push the
dipstick back in all the way.
Consistency of Readings
Always check the fluid level at least
twice using the procedures
described previously. Consistency is
important to maintaining proper fluid
level. If inconsistent readings
persist, check the transmission
breather to be sure it is clean and
unclogged. If readings are still
inconsistent, contact the dealer.
How to Add Fluid
In cold operation, Allison
recommends using Synthetic
Transmission Fluid approved to
Allison Transmission specification
TES-295 in areas where the
minimum ambient temperatures are
below 鈭40掳C (鈭40掳F).
Refer to the Maintenance Schedule
to determine what kind of
transmission fluid to use. See
Recommended Fluids and
Lubricants on page 11-8.
Add fluid only after checking the
transmission fluid while it is hot.
A cold check is used only as a
reference. If the fluid level is low,
add only enough of the proper fluid
to bring the level up to the HOT area
for a hot check. It does not take
much fluid, generally less than 0.5 L
(1 pt). Do not overfill.
 

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... Any reason why there would be excess fluid in the transmission from the previous owner? ...
Yes, somebody didn't know what they were doing.

... Does it help when towing at all? ...
As others said, it's often the cause of the Allison running hot, so no, it doesn't help.

... Should I try to drain some of that? How much fluid does the dipstick dip into, or how much fluid is it from the top of the hot mark to the top of the cold mark?
Yes, follow the methods suggested above. With a regular drain/fill on level ground it should be very close to 7.75 qts., or maybe just a little less (try 7.5 and add from there). Also, to be more specific about the hot check, at 160*F the proper level is at the bottom of the hot-hash area; at 200*F it's probably near or at the top of the hot-hash area. Many of us can't get to 200*F to check, so at about 170*F it should be about 1/4th of the way up the hot-hash area. Of course, these are all just guidelines...
 

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With a deep pan, the filter moves down and so does the amount it's submerged.

If you go back through all the threads of a Allison overheating, being overfilled is the #1 reason.

Being overfilled by 2% seems to be much worse than underfilled by 5%.

In my race cars, I always ran them a quart low too, for less windage.

Running the Allison (w/ the deep pan) halfway between the COLD and HOT lines at full temp seems to be a good compromise to me. No danger of being overfilled and still having plenty of fluid submerging the filter.

Most folks say their LML runs about 100 degrees above ambient temp.

Mine runs about 75 degrees above. ( About 145 degrees on my CTSII readout on a normal day)

It works well for me.

Yea, My LLY 5 speed and LML 6 speed are both run this way.
I'm familiar with not overfilling just hadn't heard of running one that low. Mine usually runs 70-80 degrees over ambient depending on running empty or towing.
 

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The question remains, did you check oil level at operating temperature? There is also a 'full hot' mark on there. It's another way to check on your work. It's no trick to do it when your fueling up. If you're having oil level problems, that's the next trick i'd pull. I'd be leary of the big bad claims of running low oil levels in any thing when you're pulling a trailer that ain't cheap and you are in the middle of a place you've never been before.
 

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Recently bought a used '05 Chevy 2500hd duramax with an Allison 5 speed. I checked the dipstick 3 times cold. Same reading every time. Up past the hot mark. Any reason why there would be excess fluid in the transmission from the previous owner? Does it help when towing at all? It's kinda of a long distance between the hot and cold marks. Should I try to drain some of that? How much fluid does the dipstick dip into, or how much fluid is it from the top of the hot mark to the top of the cold mark?
Unless I missed this reading your thread, was you checking the fluid level with the engine running and in park.
The spin-on trans filter holds about 8 ounces if you need to lower it a little.
 

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Discussion Starter #14
Recently bought a used '05 Chevy 2500hd duramax with an Allison 5 speed. I checked the dipstick 3 times cold. Same reading every time. Up past the hot mark. Any reason why there would be excess fluid in the transmission from the previous owner? Does it help when towing at all? It's kinda of a long distance between the hot and cold marks. Should I try to drain some of that? How much fluid does the dipstick dip into, or how much fluid is it from the top of the hot mark to the top of the cold mark?
Unless I missed this reading your thread, was you checking the fluid level with the engine running and in park.
The spin-on trans filter holds about 8 ounces if you need to lower it a little.
No i checked it cold with the engine not running in park. Theres a cold fill line. Why would they have a cold fill line if you couldn't use it?
 

LHN...We ARE the Joneses
Joined
26,254 Posts
No i checked it cold with the engine not running in park.
Needs to be @ idle, running.
 

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No i checked it cold with the engine not running in park. Theres a cold fill line. Why would they have a cold fill line if you couldn't use it?
Read this explanation below as to why starting off cold post reply number 8.
I鈥檓 pretty sure the dip stick might have a stamp on it to check with engine idling in park


Cold Check Procedure
The purpose of the cold check is to
determine if the transmission has
enough fluid to be operated safely
until a hot check can be made. The
fluid level rises as fluid temperature
increases. DO NOT fill above the
COLD band if the transmission fluid
is below normal operating
temperatures.
1. Pull out the dipstick and wipe it
with a clean rag or paper towel.
The transmission dipstick is
located near the center of the
engine compartment. See
Engine Compartment Overview
on page 10-3 for location.
2. Push it back in all the way, wait
three seconds, and then pull it
back out again.
3. Check the fluid level reading.
Repeat the check procedure to
verify the reading.
4. If the fluid level is within the
COLD band, the transmission
may be operated until the fluid is
hot enough to perform a hot
check. If the fluid level is not
within the COLD band, add or
drain fluid as necessary to bring
the level into the middle of the
COLD band.
5. Perform a hot check at the first
opportunity after the normal
operating temperature of 71掳C
(160掳F) to 93掳C (200掳F) is
reached.
6. If the fluid level is in the
acceptable range, push the
dipstick back in all the way.
Hot Check Procedure
The fluid must be hot to ensure an
accurate check. The fluid level rises
as temperature increases.
1. Operate the transmission in D
(Drive) until the normal operating
temperature of 71掳C (160掳F) to
93掳C (200掳F) is reached.
2. Pull out the dipstick and wipe it
with a clean rag or paper towel.
3. Push it back in all the way, wait
three seconds and then pull it
back out again. Repeat the
check procedure to verify the
reading.
4. Safe operating level is within the
HOT band on the dipstick. The
width of the HOT band
represents approximately 1.0 L
(1.06 qt) of fluid at normal
operating temperature.
5. If the fluid level is not within the
HOT band, add or drain fluid as
necessary to bring the fluid level
to within the HOT band.
6. If the fluid level is in the
acceptable range, push the
dipstick back in all the way.
Consistency of Readings
Always check the fluid level at least
twice using the procedures
described previously. Consistency is
important to maintaining proper fluid
level. If inconsistent readings
persist, check the transmission
breather to be sure it is clean and
unclogged. If readings are still
inconsistent, contact the dealer.
How to Add Fluid
In cold operation, Allison
recommends using Synthetic
Transmission Fluid approved to
Allison Transmission specification
TES-295 in areas where the
minimum ambient temperatures are
below 鈭40掳C (鈭40掳F).
Refer to the Maintenance Schedule
to determine what kind of
transmission fluid to use. See
Recommended Fluids and
Lubricants on page 11-8.
Add fluid only after checking the
transmission fluid while it is hot.
A cold check is used only as a
reference. If the fluid level is low,
add only enough of the proper fluid
to bring the level up to the HOT area
for a hot check. It does not take
much fluid, generally less than 0.5 L
(1 pt). Do not overfill.
 

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Discussion Starter #17
I like that last part - do not overfill. Everything that could go wrong has gone wrong with this truck. FUBAR coolant system, possible hg/egr leak, heater core leaking and transmission overfilled. Fckn trade in truck. Im trying to get the dealership to take care of these problems. Haven't even had it two weeks.
 

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No i checked it cold with the engine not running in park. Theres a cold fill line. Why would they have a cold fill line if you couldn't use it?
3rd fuggin' post in this thread said to check it while running.

I have a feeling you create your own problems.
 

Registered
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391 Posts
No i checked it cold with the engine not running in park. Theres a cold fill line. Why would they have a cold fill line if you couldn't use it?
Because if you read the first 3 sentences of the procedure I posted, you will maybe understand why there's a cold fill line. Take it to someone who knows WTF they're doing
 

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The cold fill line is just to give you a ballpark, it is not as accurate as checking when up to temp. To get an accurate reading you need to get it up to temp and then check it with the engine running and in park.
 
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