Tranny fluid change?

[withac]

You don't need to pry on the center electrode to open a gap. Slide the side electrode through the hole and pry down/away from the plug. The pressure is on the outer edge of the side electrode not the center electrode, although before I figured out I didn't need to regap the TR55's I tried and the side electrode was so stiff I couldn't move it, but I've been able to open the gap on standard plugs that way.

 

[05TahoeZ71]

Sorry to drag this back out. I'm new so let me know if I'm F'd up. Jason hopefully you haven't done your tranny drain and fill, cause I'll let you in on a couple of gotchas. Take a look at your tranny pan, if it is multi leveled, i.e. it has a deeper portion and a shallo portion to it, it's the deep pan if it's uniformly level across the bottom, it's the shallow pan. This only makes a big difference if you have the deep pan and get the shallow filter, it won't be sitting down in the fluid.

The drain and fill is really easy especially since you have a drain plug, mine didn't. After you drain it, pull of the tranny pan. This will be particularly difficult with the shift cable bracket on the driver's side. It takes a T-40, but mine was impossible to get at even with a stubby wrench, so I just bent it out of the way. With the pan off, clean it and the magnet, I use carb cleaner.

Now this is the biggest gotcha I wish I woulda known. You just pull the filter out of the valve body. There is a rubber and metal gasket up in the filter port on the valve body. If you can't pull it out with your finger, leave it in and just slap the new filter in. I almost ended up f-ing up my valve body trying to get that thing out. Slap your pan back on with a new gasket, bend the shift cable bracket back in place, and fill her up from the tranny tube under the hood. For your '06, Dexron VI is recommended and will take somewhere around 4.5 to 5 quarts.

As far as the flush goes, I would echo what everyone else has said. Also my buddies at the local GM dealership straight up told me the chemicals they flush with are really funky and tend to F up engines more than help them, so stay away. If you're looking to swap out RP, do a drain and fill, you'll only replace about 1/3 of the fluid, drive for 5k miles and do another one, then another. I would stay away from the technique of draining, filling, and turning your engine on and shifting to flush it. Yikes. Hope that helps.

 

[jasper10101010]

Thanks for the insight!

Man, I have been putting this off, but intend to change it this weekend. I really appreciate the insight you have given here. I'll have to get back under and check the trans pan. I believe, if memory serves, that the pan is uniform across the bottom, with only an indentation around the drain plug. It sounds simple enough once I figure out exactly which pan I have.

On a side note, I have an '03, not an '06, and it's not a Denali. Is the Dexron 6 still good to use? I assume so, as it should be an improvement over the old type, correct? Again, thanks for you input man, it should make things a bit easier!

Now, I just have to pull those plugs back out and re-gap them back to .040!

 

[BOSS]

Sorry to drag this back out. I'm new so let me know if I'm F'd up. Jason hopefully you haven't done your tranny drain and fill, cause I'll let you in on a couple of gotchas. Take a look at your tranny pan, if it is multi leveled, i.e. it has a deeper portion and a shallo portion to it, it's the deep pan if it's uniformly level across the bottom, it's the shallow pan. This only makes a big difference if you have the deep pan and get the shallow filter, it won't be sitting down in the fluid.

The drain and fill is really easy especially since you have a drain plug, mine didn't. After you drain it, pull of the tranny pan. This will be particularly difficult with the shift cable bracket on the driver's side. It takes a T-40, but mine was impossible to get at even with a stubby wrench, so I just bent it out of the way. With the pan off, clean it and the magnet, I use carb cleaner.

Now this is the biggest gotcha I wish I woulda known. You just pull the filter out of the valve body. There is a rubber and metal gasket up in the filter port on the valve body. If you can't pull it out with your finger, leave it in and just slap the new filter in. I almost ended up f-ing up my valve body trying to get that thing out. Slap your pan back on with a new gasket, bend the shift cable bracket back in place, and fill her up from the tranny tube under the hood. For your '06, Dexron VI is recommended and will take somewhere around 4.5 to 5 quarts.

As far as the flush goes, I would echo what everyone else has said. Also my buddies at the local GM dealership straight up told me the chemicals they flush with are really funky and tend to F up engines more than help them, so stay away. If you're looking to swap out RP, do a drain and fill, you'll only replace about 1/3 of the fluid, drive for 5k miles and do another one, then another. I would stay away from the technique of draining, filling, and turning your engine on and shifting to flush it. Yikes. Hope that helps.

Great post, thanks!

BOSS

 

[Dahlar]

I am also curious of this subject as my 02 yukon just hit 190 and I don't think the fluid has been changed since 75K or so. It sounds like I should just do a drain and filter and put in 5 quarts if Dexron VI?

 

[05TahoeZ71]

As far as I know 06 was the first year Dexron VI was recommended. I could be wrong though. I put it in my 05 at 65k miles (I've been towing quite a bit). Can't see how it can be any worse. So far the shifts have been a little stiffer, but I've also been playing around with the shift pressures on my programmer when I'm not towing. I initially put in 4 quarts and kept doing hot tranny fluid checks for a week and it took just under 5 quarts.

Jason, how many miles are on your 03? If you have over a hundred k and haven't changed the tranny fluid I would drain, swap the filter, and fill it up. If not you could just get away with a drain and fill, much easier and quicker. GM only recommends a drain and fill at 100k (as long as you aren't towing) and some of them don't even put a new filter in.

Let me know if you want more details.

 

[jasper10101010]

I'm at 100k, a little over. I bought it with around 80k, not had any issues with it, just want to keep it that way! I think I will go at it this weekend and see how it turns out. I still can't get past the refill method through the damn dipstick tube! That seems so inefficient, can't imagine not having a refill plug somewhere! Oh well, no big deal. I'll let you guys know how it turns out this weekend.

 

[OmarR]

To further add, you guys can do a flush yourself in your own garage. All you need is some clear line tubing and a large bucket from Home Depot. Flush it out through the lower line at the radiator, one/two quarts at a time.

I bought my Tahoe with 41K, I did my own flush at 50K and switched over to synthetic. Will probably do it again at 90K. Still running strong!

 

[05TahoeZ71]

Did you turn it on and run it through the gears while somebody else poured tranny fluid in? I read about something similar in another forum or a click and clack type website. I was a little wary of trying it out. Do you tow a lot to flush that often or just being safe? I'm just curious.

 

[withac]

The problems with some flushes is that they can stir up stuff that can lead to problems. I read of a way to do it so that's not an issue but I can't find where I saved it. If I recall, you take the hoses off your tranny cooler, you put the one that feeds back into the tranny in your bucket or bottles of new fluid. You put the hose feeding into the cooler into your collection bucket. You let it suck in clean fluid and the clean fluid supposedly pushed the old dirty stuff out ahead of it. You keep letting it suck in new fluid until the stuf running into your bucket runs clean. Then you know you have new, clean fluid all the way through your tranny. The article said this was better than a traditional flush because it didn't stir things up, the fluid just flowed through the tranny in the same path and direction that it always did. You may not get any sediment or whatever cleaned out this way, but you should get a complete fluid change without worrying about stirring stuff up.

FWIW.