I am going to replace the transmission filter myself and put new fluid in it too, as well as replace the pan gasket. I did a little research and found that upgrading to dexron 6 from the recommended dexron 3 is highly recommended, and is what I will be doing. But what brand should I use? I was looking at Valvoline but for no specific reason, I just happen to see it was for transmissions that use Dexron, so I was wondering if that was a good brand or if theres a better one to use. But how many quarts should I buy?? I know the torque converter holds a lot of the fluid, maybe around half, so I was thinking of flushing the tranny, then driving it for however long and flushing it again to get the rest of the fluid out that was in the TC. But how long should I drive it for to make sure the new fluid has circulated in the TC before doing the second flush? I have an 03 LS model with the 4T65E trans.

 

I'd buy 8 quarts for a pan drop. Ive not needed more than that before.

No idea on how long to drive it, I've never done a double drop back to back. The bad thing is the is your second drop is going to be almost half brand new fluid (mixed in of course) going straight into the trash.

 

Yeah thats the unfortunate part, but I dont know any other way to do it and im not sure if leaving old fluid in there is good for it or not, or even if it matters. I dont dare do a transmission flush, I heard thats not good for these old transmissions, I read it can damage them so I dont even dare attempt having a shop do it. I would rather spend $60 on 4 gallons of fluid than $2800 rebuilding my trans.

 

Practically everyone that DIYs it leaves some old fluid in there. Even 2 back to back pan drops will still have 25%ish old fluid left. I wouldnt be too worried about it unless the old fluid looks really bad.

If you're going to do 2 back to back, I'd consider getting that Dorman pan with the drain plug. Since you're obviously not going to touch the filter the 2nd time, it would sure make that drain process a lot quicker/ cleaner and would make things easier for future fluid changes.

 

Yeah I’ll look into that pan, I havent been under there and i’ve never changed any kind of fluid in the car before but I watched some videos on how to do it, doesnt look complicated at all, probably one of the easier maintenance tasks to do. I didnt know the Monte doesnt have a pan with a drain plug, thats annoying, thanks GM/Chevorlet, haha. I definitely want to make that upgrade for sure. I dont want to have to unbolt the pan and do a controlled spill every time, thats messy, thanks for the tip. Ill try to find it. I looked on the dorman site and didnt see it, but ill keep looking around.

Edit: I believe ive found it: https://www.dormanproducts.com/p-516...mfrcode=4T65-E

is that the one?

 

Yep, that's the one. IMO its a worthwhile splurge for anyone that plans to change fluid at more frequent intervals and its ideal for situations like your 2 change back to back plan.

If nothing else, it gives you the peace of mind of not having to disrupt that pan gasket any more than you have to.

 

Yeah not having to deal with that gasket is a plus, and anything that makes my life easier is always good haha, I will buy that for sure, i will be doing all my own transmission fluid changes from this point forward so thats a really good investment. Also, for anyone stumbling on this post, I read that just running the car for 5 to 10 minutes and shifting into all the different gears should be enough to circulate the fluid in the torque converter.

Thanks again for the help and the drain pan with the plug, thats going to come in handy.

 

Hi, good to see you taking on this task, pretty easy over all. What I would do during the fluid, "drain / fill / drain / fill / drain / fill" procedure as follows. Drain what I could and then NOT put in my new DEX VI, but use the cheaper DEX III for the 1st couple cycles. Thus diluting down the old fluid twice with new fluid. Then when I do the final drain cycle top off with the DEX VI. I know I'm a tight wad, but it just made more sense to me to do it this way. Also when reinstalling the pan bolts there is a certain tightening sequence to follow. And don't be overly heavy on the ratchet when tightening the bolts, they tend to strip rather suddenly if you crank a bit to much. Also when removing the filter you will find yourself twisting and pulling down rather forcefully to unseat it. Then same when reinstalling it, insure you put substantial pressure when reseating the neck. I left my old O-ring in as it was somewhat new, lo, my Monte eats trannys. Best of luck, easy cheesy and save $300 from a shop doing it.

 

Just curious, what is the price delta between a quart of 3 and 6? Ive honestly never compared them or thought of that. I guess I just always assumed they were all in the same ballpark.

 

Thank you for the heads up, I didnt know there was a specific order they needed to be tightened in. I'll have to find out what that order is somehow and the torque spec for the bolts. I have a torque wrench here i just got, but I dont know if its calibrated correctly. Being bounced around in shipping it could have come out of calibration and i dont want to risk it stripping the bolts.