Transmission level checking

[booster]

Checking the ATF level in many vehicles is kind of a lesson in futility. We have had other discussions on the topic here in the past, even.


They tell you to drive the vehicle or run the engine until hot, put it in park, leave the engine running, shift through all the gear selections while still sitting and put back in park, leave the engine running and take out the dipstick, wipe it off and put it back in, pull it out and check it.


Ok, all of that works fine right up to last step because the fluid is all over the stick end, not the same on both side, might have gaps or not, and almost transparent besides, so after all the work you kind of guess at what it is telling you.


What happens, it appears is that when you pull the dipstick out to wipe it off, it deposits ATF on the tube inside above the level. You put stick back in and pick up that fluid that is above the actual level.


My method has been to be to pull the dipstick out and wipe it off before running the engine at all, then put it back in and leave it out 3+" or just not put it back in. This prevents the bottom of the stick from getting wet during the procedure above. When done with the drive push the stick all the way in and pull it out and check. Almost always get a good clean line of the level that way.


But, it does carry some small risk as some transmission setups will "spit" ATF up the tube when hot. That is why the dipsticks have the locking mechanism on them for many/most vehicles. If it spits, it often goes bad places like on hot manifolds, etc.


What I did for my 1996 Buick Roadmaster wagon was order another dipstick, cut the old dipstick down to being only about 8" long and put it in. I then did the procedure and took out the short one and put in the long dipstick. Very nice clean line and no chance of spitting.


I now leave the short stick in place in normal use so the tube will be clean if I need to check fluid level. I put the full length dipstick in a 3/4" CPVC tube with a cap on one end. The stick seal and clamp works well on the tube ID even, so it will stay clean. The long tube fits fine in the underfloor storage in the rear of the huge wagon.









Out Chevy Roadtrek dipstick is very long, so probably would not do exactly the same, but probably would do a short tube for the short stick and carry that. The need to check fluid is rare, so would need to swap in the short one and wait for the fluid in tube to clear before checking. Minor PITA but still a lot better than guessing.

[rogerstg]

Great idea and clever. Thanks. I usually wait a few minutes after pulling the dipstick for the fluid to mostly drain from the tube. But that need to wait usually results in my putting off checking the fluid level. Like your rig, the Dodge dipstick is very long. I'll think on an easy way to store and retrieve it that works for me.

[booster]

Originally Posted by rogerstg

Great idea and clever. Thanks. I usually wait a few minutes after pulling the dipstick for the fluid to mostly drain from the tube. But that need to wait usually results in my putting off checking the fluid level. Like your rig, the Dodge dipstick is very long. I'll think on an easy way to store and retrieve it that works for me.

If the dipstick is springy enough to come back to shape you can coil it into about a 15" diameter coil and put it a bag like the jumper cable bag in pic of the Buick. That is how they ship them when you buy a new one, but the Buick one did not come back completely straight and for some reason the Buick is really difficult to get the stick in even if straight so I went to CPVC holder. When I get a new dipstick for the van I will see if it will go in OK after being coiled and if it does that is likely how it will travel.

[rogerstg]

I was thinking along the lines of some type of flexible tubing that I could mount in the engine compartment so that the dipstick is always handy. I haven't looked yet, but maybe there's a route available parallel to the rear brake line.