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Transmission Overfill?

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#1 CapitalTruck


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Posted 30 December 2006 - 09:14 PM

I had my transmission fluid changed the other day (pan and filter), they overfilled the unit by about 1/2 inch. Is this going to be a problem (i.e. should I snake a vacuum tube down the dipstick tube and suck a little out) or will it be alright? What do you think?

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#2 01z71



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Posted 30 December 2006 - 09:46 PM

I had mine doen too. They also overfilled it. I wouldn't worry about it (I'm not) because when I got the truck it was also overfilled.
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#3 CoastyAV8R



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Posted 31 December 2006 - 05:01 AM

Because it was like that when you got it doesn't make it right.

If it was mine, I would go buy some small diameter hose and stick it down the dipstick tube and suck it out until it was at the proper level using a syringe, but it ain't mine...

It seems 01z71 hasn't had any problems with his tranny being over serviced though.
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#4 95Sierra2500


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Posted 31 December 2006 - 09:20 AM

For automatics I usually try NOT to overfill them, but a little doesn't really hurt. Manuals I usually put my thumb over the hole and then start filling, when it comes out over my thumb then I plug it up...But then, a manual doesn't have a pump or anything critical to 'too much' fluid.
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#5 ken1mod


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Posted 31 December 2006 - 03:52 PM

the problem with overfilling is that the oil can rise up into the rotating machinery and be whipped into a foam which will cause destruction through low pressure.

I do not like to see a transmission overfilled. I would lower the level any convenient way.


#6 dewfpo


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Posted 31 December 2006 - 11:15 PM

If it were me I would bring the level down. I had an overfilled tranny once (by 1/2 qt.) and after a few hundred miles it started to whine. I removed the excess atf and it's been fine ever since.

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#7 C & A s Dad

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Posted 01 January 2007 - 12:46 AM

1/2 inch on the stick is a good bit. I would say this is too much and would get it out. This is a common problem when having a trans serviced. I do my own but when I have my company van serviced and make sure they leave it low and I top it off later. It seemed until I started telling them to leave it low, they always overfilled it.

My theory is there are too many people in these shops that do not understand the trans has to be at full operationg temp to check it. The check it after driving it for 2 miles and the fill it at that point. It will then be overfull once it is heated up to op temps.
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#8 ken1mod


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Posted 01 January 2007 - 04:45 PM

An interesting point is that these transmissions run quite cool in normal conditions. After driving 100 miles in Phoenix, Az, because of the lock up converter, the dipstick was only warm to the touch. Do not overfill.