I had my AT fully serviced last year. The ATF is low now and I intend on topping it off. I know it was filled with Dexron III (non-synthetic) at the service. My question is, what type of Dexron III is appropriate for topping it off? There's Dexron III/ Mercon, Dexron III H spec., and several others. I haven't found one that just says, "Dexron III". Any info would be great, thanks.

Jim,

84 928s AT 55K

 

I believe Dextron III/Mercon is recommended for the 928. I've been using it with no problems and had plain Dextron III in the tank prior to my service. I don't believe there's any issue with compatibility. Also, how low is it? Are there any leaks under the car?

 

This may have been covered in other threads, but I found an inexpensive solution to filling the trans fluid. And no, it does not require the use of a large hole saw, although......

I took a cheap pesticide sprayer (aprox 20 CAD) and removed the atomizer from the end. poured fluid into it and pumped it up to pressure. There is a on off switch on the hose for convenience. Added bonus it does not flow more than the strainer will allow into the tank. No more overflowing tanks.

Has always been a pita so thought I would share.

Oh ya, I just use any fluid that says Dextron III on it.

 

Dexron III is the grade to use; however, many of the better ATFs available today are 'multi oils' - ie., they are formulated to simultaneously comply with several different specificatiions of GM, Ford, etc. Dexron II, Dexron III, Mercon, Mercon V, are some of these other specifications met by such ATF oils ..... so as long as Dexron III is on the label, it is good to use.

 

Thanks for the info. If there's no problem topping off the Dexron III with Dexron III/ Mercon, I'll probably use that. It seems to be the easiest to come by. How low is the fluid? I'm not sure, but its not shifting out of second. Had this same issue when I got the vehicle and it was just low on ATF, real low. That's when my mechanic did the service. I still haven't figured out how I'm going to fill it. This will be my first attempt. The whole procedure seems like a B@#&*. I might have access to a lift though. That will make things easiear.

 

That would not be a problem (fluid issue). There are many methods to add fluid - none of them too easy. Be careful to clean up around the reservoir cap prior to opening.
It's best to add to a warm engine/trans and it must be running. For simple top up, I've used a syringe (25-50mls) and a short length of tubing ..... aim for the middle mark, which is ~1/4 up from the bottom.

 

Karmann,
Low fluid (and high fluid levels) can upset the box and may explain the reluctance to change - top it up and see. The box is very sensitive to level - though not quite sure why (which is probably why I'm a doctor not a mechanic!).

 

The fluid level fluctuates dramatically with temperature hence the advice on having the engine running etc. when checking level. If you clean the reservoir you should see 3 marks; MAX, MIN and 20C (top to bottom). When I recently fixed an ATF leak on my car I drained some of the old fluid and replenished the system to the 20C mark with the engine cold. Starting the engine and putting the a/t in neutral allows the fluid to flow and subsequently heat up. Then its a matter of rechecking when the a/t is warm which takes some time of engine idle while sitting the garage (good time for a cold one). Also, if you leave the fastening bolts off of the reservoir while performing the fill operation you can level the reservoir and not be so concerned about having to have the car on a lift. Using this method also saves burnt hands and fingers until you put the cap back on............ouch!

 

See my post earlier. You can use a pesticide sprayer that will easily reach under the car to fill. Also it flows at a rate that will not overflow the strainer in the fill hole. Just remove the front end that turns the flow into a mist.

Rod

 

Update:

I rigged a device to fill the reservior, no big deal. However, I noticed the leak.....pretty signigicant, several drops in a matter of minutes (hot engine). It appears to be leaking from in front of the transmission. The drops are coming from what I believe is the.... bell housing?(Forgive my lack of technical terminology, I am mechanically declined.) I noticed something about that housing that seemed strange. It has a whole in the front of it bigger than a silver dollar. Is that supposed to be plugged up??? The bottom of that housing is vented, so I figured maybe it's not supposed to be plugged. (Man, I really need the workshop manuals). Anyway, this housing appears to have a seal running along the width of it and the drops are gathering there. I will post some photo's of everything I mentioned later.
Could someone shed some light on what I saw. (It would be great if you could dumb it up a bit for me, ha)

 

That item i called the bell housing may actually be the torque converter.

 

You could have 1 of 2 problems (actually 3) First thing to check is the torque converter drain plug. Check to see if there is fluid leaking from around the plug...could be the crush ring or just not tight. This would be the best case scenerio. BTW, you would need to throw a wrench on the engine crank bolt and turn the engine clockwise (if you were facing the the engine) to get the converter drain plug visible though the bell housing grate. DO NOT use a pry bar or big screw driver like so many boneheads do!!!

If that is not the problem, then you either have a worn torque converter journel seal or the tranny pump gasket is toast. Either of these two require dropping the rear end and pulling out the transaxle. I have been down this road twice and recommend that if you are going to replace one, replace the other at the same time....we are just talking a few more bolts to pull the pump.

If you are not a guy who works on your own car, then you need to find someone to come over and help you. Getting this done by a certified mechanic is going to cost a bit of coin. I have done this job myself and had the tranny on the ground on end in less than 2 hours. It is not a difficult job if you know how to follow the manual and have the correct tools. If you are going to do this, then I can give you info on where NOT to follow the manual as their way is a bit more difficult and makes no sense

If you can live with the drips, like many do, then you will most certainly be on your back every month filling the tranny and wearing it out more quickly. The tranny NEEDS fluid all the time. Running low is NOT a good thing! I got stupidly tired of doing this routine and just did the job. No leaks and dry as a bone. I HATE leaks!!!

Good luck and you can contact me directly if you need advice on the procedure.

(ADDED) BTW, when you get the tranny tightened up with no more leaks, lose the bottom shelf fluids. Go with Royal Purple or Red Line specifically made for transaxle final drives and transmissions. You will notice better performance out of these components. You DID have the final drive fluid changed...right???

 

Thanks for the info, I hope its just the torque converter drain plug. That would be great. So, I'm guessing that the silver dollar sized hole in the front of the TC is not supposed to be plugged up? I found that strange, it looked like it should have had at least a rubber plug or something, what is it's purpose?