Transmission Service Questions

[thatryan]

Hey all, I am considering changing out all my fluids as I just hit 25k and this is mostly for peace of mind.

 

Truck is 2017 Z71, 6 SP. trans.

 

First, it appears most people do a pan drop drain and fill with gasket replace. Is that beneficial, getting some new fluid in while like 50% is still old/original?

Second in the manual for capacities, I do not see trans listed, how do I know how much it even holds total?

 

Thanks.

[Grumpy Bear]

[TXGREEK]

Hey all, I am considering changing out all my fluids as I just hit 25k and this is mostly for peace of mind.
 
Truck is 2017 Z71, 6 SP. trans.
 
First, it appears most people do a pan drop drain and fill with gasket replace. Is that beneficial, getting some new fluid in while like 50% is still old/original?
Second in the manual for capacities, I do not see trans listed, how do I know how much it even holds total?
 
Thanks.

Look into using Amsoil 100% Synthetic Fluids and not that BS Full Synthetic garbage! Full Synthetic is not 100% Synthetic, it’s a base Oil with added synthetics. Only 100% Synthetic is REAL 100% Synthetic. Your vehicle will love you for it and you’ll definitely notice the difference!

[thatryan]

50 minutes ago, Grumpy Bear said:

saw that coming...

 

32 minutes ago, TXGREEK said:

 

Look into using Amsoil 100% Synthetic Fluids and not that BS Full Synthetic garbage! Full Synthetic is not 100% Synthetic, it’s a base Oil with added synthetics. Only 100% Synthetic is REAL 100% Synthetic. Your vehicle will love you for it and you’ll definitely notice the difference!

 

Regardless of type of fluid, im wondering if there is any benefit to getting "partially" clean ATF in there, as only maybe 50% comes out from drain and fill...

[BlancoSilverado]

Yes, on the 50%ish fluid exchange. Its cleaner fluid then what you had in there.

This will help with keeping that transmission alive for longer. The old friction material will (overtime) ruin the fluid while contaminating it and hurting the clutch packs if not addressed. this will usually happen after 150k miles the clutches are done and at that point you want to just keep that fluid in there because that fluid might be keeping the clutch packs working (this is what i've been told for years and multiple vehicles).

 

I personally will be changing out my fluid (roughly 5 quarts) every 30K miles or sooner, matters on how i feel about the pressure i put on the transmission.

[kickass audio]

When I siphoned out my pan before I dropped the pan to replace the filter I think I drained out around 4.5-5 quarts of fluid. You still have more than that in your torque converter so remember that. I did not replace the gasket as it was in flawless condition so just don't cut it up or anything that would ruin the seal and you can reuse it.

 

One tip with dropping the pan is to first siphon out the fluid from the pan if you can so you don't wear a ton of the transmission fluid. Then remove all the bolts holding the pan on. Next with the pan loose from the body of the trans take the rubber gasket and spin it sideways away from the pan, you don't want the gasket on the reward part of the pan since that is where it will get bound up with the exhaust. With the gasket at like a 45 degree angle drop the front of the pan down and then wiggle around the rear of the pan to get it past the exhaust and filter. Take your time so you don't snag the gasket or ruin any lines in the trans.

 

I didn't need to loosen or remove any parts of the exhaust at all. I tried to loosen both the bolts securing the trans mount to the frame and jack up on the trans but that doesn't give you any extra room between the pan and the exhaust so don't waste your time.

[thatryan]

20 minutes ago, kickass audio said:

When I siphoned out my pan before I dropped the pan to replace the filter I think I drained out around 4.5-5 quarts of fluid. You still have more than that in your torque converter so remember that. I did not replace the gasket as it was in flawless condition so just don't cut it up or anything that would ruin the seal and you can reuse it.

 

One tip with dropping the pan is to first siphon out the fluid from the pan if you can so you don't wear a ton of the transmission fluid. Then remove all the bolts holding the pan on. Next with the pan loose from the body of the trans take the rubber gasket and spin it sideways away from the pan, you don't want the gasket on the reward part of the pan since that is where it will get bound up with the exhaust. With the gasket at like a 45 degree angle drop the front of the pan down and then wiggle around the rear of the pan to get it past the exhaust and filter. Take your time so you don't snag the gasket or ruin any lines in the trans.

 

I didn't need to loosen or remove any parts of the exhaust at all. I tried to loosen both the bolts securing the trans mount to the frame and jack up on the trans but that doesn't give you any extra room between the pan and the exhaust so don't waste your time.

Thanks for the tips!

 

yeah I knew that a ton would still be on the converter, which is why I was curious if it’s beneficial to replace just some of the fluid.

 

So there  is no drain plug on these pans? I have not looked yet lol. How did you siphon out?

[kickass audio]

21 minutes ago, thatryan said:

Thanks for the tips!

 

yeah I knew that a ton would still be on the converter, which is why I was curious if it’s beneficial to replace just some of the fluid.

 

So there  is no drain plug on these pans? I have not looked yet lol. How did you siphon out?

I siphoned it with my mityvac pump. It's a manual pump kind of like an old school bicycle pump but mine can dispense and vacuum fluids so it's really handy. Just go in through the dipstick tube and drain as much as you can out. You can skip it if you wanted to but you will get a bath in trans fluid so I would recommend evacuating it as much as possible through the dip stick before you loosen and drop the pan as you have a good fight to get the pan out around the exhaust and the filter still in the trans.

 

Being you are low mileage a drop and refill would be fine. I chose to do a drop and refill with a new filter and then disconnected the cooler line on the drivers side of the radiator and pumped the fluid in a bucket until it came out bright red like what I was pouring in. I was at 54k miles though so I chose to flush it out as much as I can to keep up on it.

 

The gasket on the pan has two little nipples that align up when you get the pan reinstalled so going the route I did with having the gasket loose so you have that extra 1/8" of room to drop the pan was very helpful as the gasket is out of the way. Once you clear the exhaust pipe and filter you can turn the gasket so it's into position and place the two nipples in the small holes drilled in the corner of the pan and then put the pan up and start bolting it in. That exhaust pipe and clearing the filter in the trans is the hardest part and it wasn't that bad to do. Just be careful and make sure you have a good grip on the pan, I goofed up and had my hands get oily and it slipped out of my hand when I managed to wiggle it free and I dropped the empty pan in my catch container and splashed it everywhere lol.

 

edit: Get a few large cardboard boxes to lay on the ground if you value your driveway looking clean and wear some crappy clothes as you will definitely get dirty on this job.

Edited September 25, 2019 by kickass audio

[thatryan]

Side note, what fluid did you use? I prefer to use the OEM AC Delco stuff, know any good places online for better prices than dealer would have?

[kickass audio]

I bought 4 of the 1 gallon jugs of dexron vi, I wish I did 5 gallons though but it was fine. I bought it off amazon as it was the cheapest one I could find aside from going to advance auto for the fluid but they only have the single quarts so you get a better deal on the big gallon containers. https://www.amazon.com/gp/product/B01EKMGG92/ref=ox_sc_act_title_1?smid=A3B850ZGIPDG3A&psc=1

[Eddie 70]

 

 

This is how I do mine. I bought a pump at Wally World and then some stiff tubing at Home Depot about 4 feet long. I keep an empty 1 gallon jug to pull the old stuff into. Then I just refill pouring it back in through the dipstick tube, of course.

[CombsL83]

6 hours ago, TXGREEK said:

 

Look into using Amsoil 100% Synthetic Fluids and not that BS Full Synthetic garbage! Full Synthetic is not 100% Synthetic, it’s a base Oil with added synthetics. Only 100% Synthetic is REAL 100% Synthetic. Your vehicle will love you for it and you’ll definitely notice the difference!

 

I feel like you have this copied and ready to paste.

[TXGREEK]

I feel like you have this copied and ready to paste.

It’s made a difference for me and that’s what forum discussions are all about, sharing information that’s relative to discussions. Besides, you’d be surprised as to just how many people are unaware of the Misleading Marketing tactics fooling the consumer into believing they’re purchasing 100% synthetic when they’re NOT!

[Black02Silverado]

9 hours ago, thatryan said:

Hey all, I am considering changing out all my fluids as I just hit 25k and this is mostly for peace of mind.

 

Truck is 2017 Z71, 6 SP. trans.

 

First, it appears most people do a pan drop drain and fill with gasket replace. Is that beneficial, getting some new fluid in while like 50% is still old/original?

Second in the manual for capacities, I do not see trans listed, how do I know how much it even holds total?

 

Thanks.

You can use the AMSOIL look up guide to help with capacities.

 

This is what is listed for your truck.

Capacities: 6 speed With HD Cool 6L80 Total Fill 12.4 quarts
6 speed 6L80 Total Fill 12.2 quarts
6 quarts Initial Fill

 

 

[thatryan]

Thanks for all the info guys. 
 

I’ll probably do a pan drop and filter change and put ac delco back in for now. Though once warranty is up I’ll probably move fluids to amsoil.