several trans rebuilders here in the st.louis mo. area have told me they run GM vehicals about pint to half a quart over the full level an the dip stick. why would anyone do this ? even two guys a know fairly well told me the same thing. must be a reason of some kind for it.
overfill
- Thread starter hardheaded
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Probably not going to hurt a half a quart, maybe they're more worried about under filling. Here is an interesting article about how over filling caused a severe over heating issue.
https://certifiedtransmission.wordpress.com/2013/03/19/6t75-overheats/amp/
https://certifiedtransmission.wordpress.com/2013/03/19/6t75-overheats/amp/
In changing out my trans fluid this past summer I got a lot of experience in trying to get the level "just right" and perfectly at the full mark. But it took a couple of tries to get there. What I learned was that just a little bit overfill (4 oz) was enough to push the oil level up into the dip stick tube. That didn't seem to be a good place to be imo.
The trans designer also put in a retainer at the bottom of the tube to keep from getting big things into the trans fluid pan. While a dipstick gets by the retainer, a plastic tube will not. So via the tube, I can only pump out few oz below "full."
Everything in the owner's manual says not to overfill...more like warnings. I take that to mean it's serious, probably more so than overfilling engine oil.
The trans designer also put in a retainer at the bottom of the tube to keep from getting big things into the trans fluid pan. While a dipstick gets by the retainer, a plastic tube will not. So via the tube, I can only pump out few oz below "full."
Everything in the owner's manual says not to overfill...more like warnings. I take that to mean it's serious, probably more so than overfilling engine oil.
Originally Posted By: 901Memphis
Probably not going to hurt a half a quart, maybe they're more worried about under filling. Here is an interesting article about how over filling caused a severe over heating issue.
https://certifiedtransmission.wordpress.com/2013/03/19/6t75-overheats/amp/
3 quarts over filled is quite a lot. I'm surprised that it only registered 1/4" higher on the dip stick. On my stick the entire low/full cross hatched area is in the 1/2 to 1" range. A 1/4" high would be a fraction of a quart. After my June trans fluid change I must have checked the level a dozen or more times over the next week to ensure it was a good reading and consistently repeated. I didn't want to be overfilled by any amount.
Probably not going to hurt a half a quart, maybe they're more worried about under filling. Here is an interesting article about how over filling caused a severe over heating issue.
https://certifiedtransmission.wordpress.com/2013/03/19/6t75-overheats/amp/
3 quarts over filled is quite a lot. I'm surprised that it only registered 1/4" higher on the dip stick. On my stick the entire low/full cross hatched area is in the 1/2 to 1" range. A 1/4" high would be a fraction of a quart. After my June trans fluid change I must have checked the level a dozen or more times over the next week to ensure it was a good reading and consistently repeated. I didn't want to be overfilled by any amount.
I overfilled the tranny on my 98 Sienna a few times. Never had an issue.
Originally Posted By: 901Memphis
Probably not going to hurt a half a quart, maybe they're more worried about under filling. Here is an interesting article about how over filling caused a severe over heating issue.
https://certifiedtransmission.wordpress.com/2013/03/19/6t75-overheats/amp/
Interesting article. The transmission in question was 1/4" high on the dipstick. They removed 3 quarts to get it to the full mark. That seems like a lot of fluid for 1/4" over the full mark. It must have one big pan.
Probably not going to hurt a half a quart, maybe they're more worried about under filling. Here is an interesting article about how over filling caused a severe over heating issue.
https://certifiedtransmission.wordpress.com/2013/03/19/6t75-overheats/amp/
Interesting article. The transmission in question was 1/4" high on the dipstick. They removed 3 quarts to get it to the full mark. That seems like a lot of fluid for 1/4" over the full mark. It must have one big pan.
I run one qt over for peace of mind
People fail to check the level with the engine running!
Originally Posted By: Ohle_Manezzini
People fail to check the level with the engine running!
Yes. But, you can also check it cold once you've established the "hot" full level. For my automatic at cold, the full mark is quite a bit higher, at the letters "ss" in the phrase "cross hatched area" printed on the dip stick. I check it both ways and they stay consistent.
People fail to check the level with the engine running!
Yes. But, you can also check it cold once you've established the "hot" full level. For my automatic at cold, the full mark is quite a bit higher, at the letters "ss" in the phrase "cross hatched area" printed on the dip stick. I check it both ways and they stay consistent.
Yeah, my GM 4T65E tranny came from the dealer with a 1/2" overfill on the dipstick that turned out to be 1 quart when I sucked out the excess.
If anyone removed 3 quarts, they'd be too low and risk a problem.
If anyone removed 3 quarts, they'd be too low and risk a problem.
all of the people i've talked to said to get it at the full mark hot and then add 1 pint to 1/2 quart. i was wantint to what would be the benefit to this. i really don't see any, but these guys were trans builders.
Originally Posted By: Ohle_Manezzini
People fail to check the level with the engine running!
None of the owner's manuals for my cars with automatics say to check it with the engine running. They say immediately after shutdown with the engine at operating temperature. One should follow the procedure in your manual whatever it is.
People fail to check the level with the engine running!
None of the owner's manuals for my cars with automatics say to check it with the engine running. They say immediately after shutdown with the engine at operating temperature. One should follow the procedure in your manual whatever it is.
Originally Posted By: i_hate_autofraud
Yeah, my GM 4T65E tranny came from the dealer with a 1/2" overfill on the dipstick that turned out to be 1 quart when I sucked out the excess.
If anyone removed 3 quarts, they'd be too low and risk a problem.
That sounds about right. But a 1/4" high on the stick being 3 quarts over, I strongly doubt it in a passenger car.
Yeah, my GM 4T65E tranny came from the dealer with a 1/2" overfill on the dipstick that turned out to be 1 quart when I sucked out the excess.
If anyone removed 3 quarts, they'd be too low and risk a problem.
That sounds about right. But a 1/4" high on the stick being 3 quarts over, I strongly doubt it in a passenger car.
all my GM vehicals state to check them idling in park and trans hot.
Originally Posted By: hardheaded
all my GM vehicals state to check them idling in park and trans hot.
Same thing all my Fords/Lincolns/Mercurys have stated over the past 30 years.
My current Lincoln manual says to REMOVE excess fluid if its above the "dot/hole" at the top of the cross hatched area on the dip stick. That would allow very little excess fluid, only a 1-4 ounces at most.
all my GM vehicals state to check them idling in park and trans hot.
Same thing all my Fords/Lincolns/Mercurys have stated over the past 30 years.
My current Lincoln manual says to REMOVE excess fluid if its above the "dot/hole" at the top of the cross hatched area on the dip stick. That would allow very little excess fluid, only a 1-4 ounces at most.
Originally Posted By: hardheaded
all my GM vehicals state to check them idling in park and trans hot.
I check my Jeeps the same way.
all my GM vehicals state to check them idling in park and trans hot.
I check my Jeeps the same way.
Originally Posted By: demarpaint
Originally Posted By: hardheaded
all my GM vehicals state to check them idling in park and trans hot.
I check my Jeeps the same way.
Supposed to make sure they are hot by driving it for an hour or two in regular traffic and let idle, as you say. As hot as possible for operation but not immediately after a highway trip, hence the idling.
Originally Posted By: hardheaded
all my GM vehicals state to check them idling in park and trans hot.
I check my Jeeps the same way.
Supposed to make sure they are hot by driving it for an hour or two in regular traffic and let idle, as you say. As hot as possible for operation but not immediately after a highway trip, hence the idling.
i run mine up the road about five miles and back to warm the trans , that's plenty.
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