DIY Auto Transmission Fluid Replacement?
 

I am looking for a DIY transmission fluid replacement on a C5, i am really looking for pictures on where the full plug is or where the sending unit is, thanks

Have fun with that, definitely not an easy DIY unless you have a lift.

The filler/cap is either on or near the tranny (never did it myself, just watched) so jack-stands will be a PITA. I can't remember the exact procedure, but after you fill it to a certain point you have to start the car and let it run while you top it off.

you can not flush all the trani fluid out of your trani without a flushing machine like the GM dealerships and some trani shops have. Best you can drain out yourself is about 30%.

invest in a drill pump..... then stick the hose into the hole....

home depot or lowes sell drill pumps for like 10 bucks...

Fill plug is on driver's side of trans pan. Full is when fluid comes out the hole with the engine running and trans in Park.

any pictures would help, i looked on the pan and didnt see anything other then the drain plug, thanks

I'm doing a refill in my '99. The drain plug is the fill plug it seems. I think there should be a tube going up attached to the plug so that the level will be higher than the level at the plug in the pan. I guess there is no way to check the level unless you fill it and see how much it takes. Mine has been leaking from the back near the pan for a long time.

To check for proper automatic trans fluid level, the car must be running and be up to temperature.

It helps to have the car up on a lift, but it can be done with the car properly supported on jack stands.

Fluid will be HOT and you are working in close proximity to the HOT exhaust pipe. Wear mechanics gloves and protect your arms.

The drain plug and fill plug are one and the same.

1. With the transmission up to temperature, the car RUNNING, and the car level; shift through all the gears, finally placing the trans in “Park”.
2. Keep car running. (In “Park”)
3. Remove fill plug. Proper level hot is just at the bottom of the drain/fill hole. Add fluid to the point that it trickles out of the drain/fill hole.
4. Reinstall plug bolt.

Flushing the fluid is another matter. Yes you must have a machine to “fully” flush the fluid. Removing the pan and changing the filter will only remove a fraction of the fluid. (1/3? ½?)

If it were me, I would insist on watching the procedure to be sure they are actually doing the flush, but that’s just me.

this is doing an automatic transmission right? thanks

The pump is a good idea. Really helps to get most of the fluid out before dropping the pan for filter replacement. I advise you to get a service manual and not rely on procedures and pics online. You can follow it step by step and do the job right every time. :thumbs:

Yep...this is for an automatic, and like he said.....drain plug and fill plug are the same.:thumbs:

Automatic Transmission Fluid/Filter Replacement

Removal Procedure

Caution
When the transmission is at operating temperatures, take necessary precautions when removing the check/fill plug, to avoid being burned by draining fluid.

Attachment 48178634

1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
2. Place a drain pan under the transmission.
3. Clean any dirt from around the transmission check/fill plug.
4. Remove the transmission fluid check/fill plug and allow the fluid to drain.

Attachment 48178635

5. Support the transmission oil pan.
6. Remove the transmission oil pan bolts.
7. Loosely reinstall the fluid check/fill plug.
8. Lightly tap the oil pan with a rubber mallet or pry gently in order to loosen the pan.
9. Remove the transmission oil pan.
10. Drain the remaining fluid from the oil pan.

Attachment 48178636

Important
Note the position of the filter before removal to aid in installation.

11. Grasp firmly while pulling down with a twisting motion in order to remove the filter.

Attachment 48178637

12. Remove the filter seal. The filter seal may be stuck in the pump, if necessary, carefully use plyers or another suitable tool to remove the seal.
13. Discard the seal.
14. Inspect the transmission fluid. Refer to Transmission Fluid Checking Procedure .
15. Inspect the transmission fluid filter. Pry the metal crimping away from the top of the filter and pull apart. The filter may contain evidence for root cause diagnosis:

o Clutch material
o Bronze slivers indicating bushing wear
o Steel particles

Important
Remove ALL traces of old gasket material from the transmission case and the oil pan gasket surfaces.

16. Clean the oil pan gasket mating surfaces, on both the transmission case and the transmission oil pan, with solvent and air dry.

Installation Procedure

Tools Required
J 36850 Transmission Assembling Lubricant (Transjel™)

Attachment 48178638

1. Coat the new filter seal with a small amount of J 36850 or equivalent.
2. Install the new filter seal into the transmission case. Gently tap the seal into place using a suitable size socket.

Attachment 48178636

3. Install the new oil filter into position as noted during removal.

Attachment 48178640

4. Inspect the oil pan bolts and washers to determine if the conical washers are reversed.

o Reuse the oil pan bolts and washers if the conical washers are NOT reversed (1).
o Replace the oil pan bolts and washers if the conical washers are reversed (2).

Attachment 48178635

5. Install the new oil pan gasket to the oil pan sealing surface.
6. Position the oil pan to the transmission case and support the oil pan.
7. Install the oil pan bolts. Tighten the transmission oil pan bolts alternately and evenly to 11 N·m (97 lb in).

Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

Attachment 48178634

8. Remove the transmission fluid check/fill plug.
9. Fill the transmission with DEXRON®-III automatic transmission fluid through the check/fill plug hole until fluid begins to pour out, then install the check/fill plug hand-tight.
10. Complete filling the transmission with fluid to the proper level. Refer to Automatic Transmission Fluid Level Check/Fill .
11. Inspect the oil pan gasket for leaks.

Automatic Transmission Fluid Level Check/Fill

Inspection Procedure

Attachment 48178634

1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
2. Start and run the engine at idle.
3. Apply the brakes.
4. Shift the transmission into each gear for at least 2 seconds per gear.
5. Shift the transmission into NEUTRAL and continue to idle the engine for 3 minutes to stabilize the transmission fluid level.
6. After allowing the fluid level stabilization time and while still in NEUTRAL (engine still running at idle), check the transmission fluid temperature on the driver information center. Specification
Transmission fluid level temperature: 30 to 50°C (86 to 122°F)
7. If the fluid temperature is above specification, turn off the engine and allow the transmission to cool, then repeat the procedure to this point before proceeding.
8. With the engine still running at idle, loosen the check/fill plug on the LH side of the transmission oil pan.
9. Inspect the fluid level:

o Any excess fluid will drain when the check/fill plug is loosened.
o If no fluid drains, remove the check/fill plug and fill the transmission with DEXRON®-III transmission fluid until the fluid begins to overflow.

10. Install the check/fill plug. Tighten the fill plug to 30 N·m (22 lb ft).
11. Shift the transmission into PARK.
12. Release the brakes.
13. Turn off the engine.
14. Lower the vehicle.

Thanks for the information. I have one question, the fill plug seems very low on the trans to be the level the fluid is supposed to be at. It's right near the bottom of the pan, there couldn't be more than a couple quarts in there before it would be flowing over that hole it seems like.
I'll be doing the job today after having to order the filter and gasket yesterday.

Your observation is correct.

However - also be aware that the dip stick in an automatic transmission (on any car) DOES reach down into the pan.

Notice that the procedure to check the fluid level specifies the engine has to be RUNNING. This ensures that the internal hydraulic system in the transmission is "primed" or "filled" with hydraulic fluid.

If you took the drain plug out of the transmission with the engine OFF you could (depending on how long the engine was off) get quite a bit of hydraulic fluid coming out of the drain plug.

:cheers:

Good reminder to all reading this thread. I did highlight the word RUNNING in my "first" post, but it is easy to overlook.

This procedure really sucks specially if you have 3" exhaust like I do. I have had a flush done by a buddy at Chevy with RP a year ago but I had to add a bit cause I added a big trans cooler. I had the ever loving crap burned out of me! Then I got smart and wrapped it with exhaust wrap.

Shahram

I had to top the tranny fluid off last summer in the wife's A4 when I put in the TC and 3.42 gears along with a tranny cooler. Let me tell you that this procedure sucks even with a lift.

Never remove the plug without the engine running unless you purposefully want to empty the tranny of a large portion of the fluid. And be careful doing a fill with the engine running as that exhaust gets hot quickly.

:lurk: