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AW4 Transmission and fluid level problems

Tryfan

NAXJA Forum User
Location
New York
This is my first time on this forum and I wondered if any one could help me with these issues. I changed the transmission fluid (only drained the pan) in my AW-4 (2001 XJ) the other day and added about 2qt of Dexron III/Merc which brought it up to about max when cold. About 4 inches further up the dipstick there is a max when hot check in neutral mark. It seems to me that is a lot of fluid expansion. Anyway after driving the jeep to hot and checking it in neutral the level really didn't increase very much. So I added more fluid and after adding about 6qt in total which I know is far too much it got close to the max when hot in neutral mark. Yesterday I started to get transmission fluid pour out of what seems the front of the transmission housing near where it meets the rear of the engine oil pan. The fluid was dropping onto the hot exhaust and smoking badly. I wonder if I have the right dipstick or what your experiences are regarding the levels on the dipstick. I will try and post a picture later. I have drained two quarts of transmission fluid out and it is not leaking as much. I checked the breather hose in the engine compartment and it seemed that there was some residual fluid there too. I am concerned in case I have blown a seal somewhere, pump failure etc. Thanks for any suggestions.
 
The cold and hot marks are 4 inches apart? I don't think so, no kind of fluid expands that much. Look at it closer, I think there's a section in the owner's manual on dipstick markings.
 
yes, re-check the dip stick markings. as for the fluid leaking, the aw4 has an overflow tube that is probably right were you are seeing the fluid. when the trans warms up the fluid will leak out the overflow. but this does not mean you now have to correct amount of fluid. you will most likely need to drain some of the fluid. do it before you really do blow a seal.
 
Dropping the pan the most you should have added would be 3.5, 4 quarts TOPS. Once you overfilled it when hot it puked out the dipstick tube. Clean up the mess, try again.
 
What's the proper procedure for checking the fluid? The owner's manual says to drive at least 15 miles to get it to operating temperature, 170*F (I think), then go through all gears and back into park. But, the dipstick says to check in neutral. So, which is it? I check in Park like the owner's manual says.
 
Dropping the pan the most you should have added would be 3.5, 4 quarts TOPS. Once you overfilled it when hot it puked out the dipstick tube. Clean up the mess, try again.
X2, I put a 5+ (hey, it's what they call it, the big jug!) quart jug of fluid into an XJ every time I drain the pan + replace the lines, and it's usually a little overfull but not too bad. The extra fluid is due to the lines being drained/replaced.

What's the proper procedure for checking the fluid? The owner's manual says to drive at least 15 miles to get it to operating temperature, 170*F (I think), then go through all gears and back into park. But, the dipstick says to check in neutral. So, which is it? I check in Park like the owner's manual says.
Get it to op temp, put it through all the gears (I like to leave it in each gear for 5-10 seconds) a few times to make sure there isn't any trapped air in the valve body, then check however the dipstick says to check it... with the e-brake set.

Remember that the dipstick tube will be coated well with fluid on the inside since you just dumped a few quarts down it. Let it sit for a while so that drains down and you get a clean reading.

Dipstick overrides manual, since the dipstick was made/supplied/spec'd by the transmission manufacturer.
 
Checking it in Park is fine. If you can get a helper to hold the brakes or you block your wheels you can check it in Neutral too.

Are you checking it with the motor running? or just hot. It has to be running.

And X2 on what joe_peters sez. With the motor off and warm (not hot), you should get about 3.5-4 qts. out of the pan. I just did this fluid change and measured the outflow and made sure the input matched.
 
3.5 quarts is about what you get with a simple pan drain. Overfilling is bad news for the tranny!!

You need to play around and practice and learn how to read the transmission dipstick. Sounds simple but is not uncommon for people to read these incorrectly.

Get a rag, wipe it down, reinsert and remove until you see where the line is. Check fluid level with engine and transmission completely warmed up and transmission fully exercised. Level lot.
 
Yes, and another good technique is the 'shortstick'. Sometimes the residual fluid in the tube from filling it will give a false high reading. Note the apparent fluid level with the stick all the way in, then wipe it clean and try again but don't seat it all the way, stay a half inch out- the level should then be a half inch lower on the stick. If not it's all residual oil giving a false reading, wait ten minutes and try again.
 
I want to try an upload a picture of the dipstick from a file I have but can't figure out how to do it - new to the forum
 
Do you need a disconnection tool to remove the tranny lines if so what size (2001 XJ with AW-4 transmission). I wanted to check if I have a blockage in the lines
 
To be honest, I don't fully understand how to read the dipstick on the 95 either. It has a line for low, then about an inch or so above that it has a small hole, then about 1/4" above the hole it has about an inch of crosshatches, then at the top of the crosshatches it says "Full". The way I read it is if the hole is empty then it's low and I fill it back up into the crosshatch area. The dipstick in the AW4 portion of the FSM I think is a stock photo and isn't XJ specific.
 
Whats the main issues going to be with overfilling the tranny

Aeration. The level will be high enough to get caught up in the rotating parts and the fluid will be whipped into foam basically. Fluid doesn't compress so well, air does- you can guess what happens with aerated fluid.
 
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