I changed my tranny fluid and filter and it now shifts like it is supposed to. It doesn't hunt for gears as much. Just better all around. It had 50,000 miles on it and the filter looked kind of dirty to me.

 

That's been on my mind for the last week or so. That and cutting cooling holes in the hood and getting real louvers for heat evacuation.

 

Well I did the fluid and filter change this morning, this is how I did it and it seemd to work fine for me,
I did this on the driveway with the front on ramps and the rear on the ground, the angle of my driveway keeps the vehicle level. It should be as level as possible for this.
Drop the skid plates, remove the transmission cooling line on the left (drivers)side of the bottom of the radiator,
There is a plastic retainer ring you slide back with a screwdriver, then you need to remove this tiny wire spring clip that holds the aluminum tube in the radiator. DO NOT LOOSE IT!. swing the tube down out of the clip and pull it back out of the radiator. Fluid will start to run out be ready.
Put a peice of tubing on the removed tube and secure it so it is aimed into a 5 gallon bucket. If you can have someone start the engine while you watch the fluid pump out, as soon as you see it sputtering shut the engine off. you should have about 5-6 quarts in the bucket.
Now you can drop the pan, there will be about a quart left in the pan, less messy than just droping the full pan.
Drop the pan, clean it and the magnet and get the gasket ready to go back on.
Pull the filter down as you wiggle it side to side. look up where the filter tube goes up into the transmission and replace the seal in there (if it came with your filter and gasket). a little tough to get out and I found a socket that was exact size of the new seal and I tapped the new one in with the socket and extension.
Replace the filter and reinstall the pan. be sure to torque these properly as to tight will deform the pan and it will leak.
Now add 5 quarts of trans fluid and have someone start the engine and you need to have 3-4 quarts ready and open to start pouring in the fill tube as soon as the engine starts, have someone watch the fluid pumping into the bucket in 4-8 seconds you will see clean fluid comming out,
Shut off the enging as soon as you see clean fluid,
Reinstall the cooling line into the radiator, be sure to get that little evil clip back in properly and slide in plastic retainer clip back on and your done under the vehicle.
Fill the transmission with the engine off until you see the proper level on the dip stick.
start the engine and with your foot on the brake shift to D and then back to R waiting about 30 seconds in each, do this a few times and recheck you fluid level.
Get it up to the cold level while the oil is still cool, engine running and in park.

Take it for a easy test drive and when it is up to operating tempature recheck the level of the fluid while the vehicle is running in park and on a level surface.
I had 12 quarts on hand and wound up using about 11 (depends on how much you let it pump when the clean fluid starts comming out)
Dont forget to put the skids back on,
This methiod worked well for me, I did the same procedure on my Envoy 6 months ago and all is well.
Good luck
and just ask if you have any questions, I will be happy to help if I can.
John

 

Did you have to remove the front driveshaft to drop the pan ?

 

Thanks for all the useful info here gents. I just bought my H3 with 47k miles last week. A full fluid change is my project this weekend. Can someone describe what the in-pan trany filter looks like. When I google it there seems to be a few diffent returns. I would prefer to not be looking into the bottom of my transmission and realize I'm holding the wrong replacement filter in my hand. Thanks in advance for the help.

 

You do not have to drop the front drive shaft, you will need to get at the 5 - 1/2" bolts on that side with a wrench, its not to bad, also on the driver side of the pan there is a bracket holding the shift cable, I took out the rear bolt and pulled it away from the pan about a half inch this gives you the room to drop the pan. Pumping the fluid out as described makes for a easy removal as you do not have all the fluid running out. there will still be about a quart in there so lower it carefully.
ACDELCO PROFESSIONAL 24225323 Transmission Filter | eBay
This is the link to the filter I used it was OEM exact fit.

 

Doc, just caught your comment about changing tranny fluid every 100k. Thank you for stating this. I am about to do my first drain and filter on my 06 h3. Its at 102,000 miles, been getting worried because of so many people talking about changing it so much earlier. I have had my 06 since 08 and even at 100k fluid still looks good and smells and flows good. Do you have any recommended fluid brand to use? I changed to royal purple in my engine and have dramatic temperature improvement!! Its almost unbelieveable. So i was considering this in atf. But worried about mixing with what would be left in trannsmission after change. Any advice would be great thanks.

 

that machine cost me 1100.00 last time it was used on my Ford Expedition. The tranny got all the gunk inside of it wedged into the channels inside the transmission. -see bobistheoilguy.com- for in depth explanation of how bad this tranny machine is...
I change my tranny fluid the same way and it has worked for me....

 

followed previous instructions but needed to drop drive shaft and plate on drivers side of transmission , just loosed shaft from front and held it up with a coat hanger out of the way , two bolts 13mm to remove plate on drivers side of tranny making it easier to reinstall pan still need to torque pan bolts (not sure of sequence ) and u-joint bolts but it should be all down hill from now , wanted quote from several mech. shops to do flush and filter change , did not get it so doing it myself I am too old for this

 

Used the suction device from my jet ski to suck out what could be gotten out. About 3 or 4 quarts. Then replaced what was taken out...

Low tech low risk...