transmission overfilled or what?


Original poster
Mar 30, 2012
5.3L v8 vortec in 2006 Trailblazer. Here is my dilemma: At 75F tranny temperature, on a level surface, the fluid is about 1/16th inch below the lower cold pair of holes in the tranny dipstick. This would indicate my transmission is slightly under-filled. At 175F tranny temperature, the fluid is about 1/2 inch above the top hot pair of holes. This would indicate my transmission is over-filled. Sometimes towing up a hill, I've seen 195F, which seems to mean my tranny would be even more 'over-filled' than I see at 175F. What is the deal? How can I be both under and over-filled? How am I supposed to interpret this?

My concern here is that we are getting ready to tow 5200 lb trailer to Yellowstone from Florida. Would kinda want to be assured that the tranny is properly filled.

Thanks for any expert/knowledgeable feedback on this [very important to me] question.



Nov 20, 2011
The fluid should be checked at "normal" operating temp, on level ground with engine at idle.

The fluid level should be within the "normal" range.

The only reason I can think of, to answer the question of why they (any trans designer) would provide a "cold" line on the stick, must be just to give a starting (actually stopping) point if the fluid is changed; that is, full to the cold line as a guide, warm up the tranny and check from there.

BTW, there is only about a pint between cold and hot

AFAIK, normal operating temp, for the 4L60E, is 175F to 190F


Jan 24, 2012
We have hot and cold on our tranny dipsticks? I thought we had a cross hatching and the fluid had to fall between that threshold while in idle after driving for ~5 minutes or so. I don't even think I have holes in my dipstick... V8 and I6 have the same tranny, don't we? I do have the 4L60E.


Nov 20, 2011
Milwaukee, Wisconsin
IIRC, the I6 and the 5.3 have the same trans. The 6.0 is different.


Jan 24, 2012
Then the dipstick must have been redesigned, just as everything else.

Regardless, check the tranny at idle after driving. The longer trip the better because it will be at operating temperature. (Tranny guy told me after changing my sungear reactor shell)
Mine is about 1/2" over the full mark threshold when hot (I don't tow though) and it's been shifting like a champ. I also have a deep pan.

And I thought the difference between Cold and Hot is 1 Quart, not 1 Pint.

Boricua SS

Nov 20, 2011
yup, the 6.0L have the 4l70e's....

same as you all are saying though... check it on a level surface, up to operating temps, and at idle... the cold readings crap is goofy, and IMO shouldve never been put there in the first place since youre always supposed to check from normal operating temps anyway..


Dec 4, 2011
I have eye-checked the cold level transmission fluid readings ever since my first vehicle. usually just to see if any is in there when I have no intention of driving that day and have not checked in a while. Of course the operating temperature reading is the tried and true method. Idle, level ground, operating temp and ac is supposed to be off. If you were towing or running the truck hard, let it stabilize. One day maybe they will improve the dipstick to an electronic means.

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