08 Transmission Flush

[Brian750]

This may be in wrong section feel free to move....
I have an 08 Tahoe I bought last year in Dec. I keep the oil changed every 3000 miles but I don't know if the trans or diff fluids have ever been changed. It has 144k on it so my question is what does everyone recommend when it comes to trans service. Just filter change and new fluid or new filter, flush and new fluid?

Appreciate any info you all have for me.

 

[Doubeleive]

try running a carfax on it if it was serviced at a dealer or national company it may show when it was done last. otherwise there is mixed opinions on what type of service to do with the transmission.

 

[sumo]

Make it easier on yourself for the future. Add a PML pan with a drain plug. It holds more fluid and is finned to help with cooling. It’s a messy job and can be a pain in the ass depending how you maneuver the exhaust.
I drain and fill 30k and the next time I do a complete trans service with a filter the next time trans is due.

 

[Brian750]

Make it easier on yourself for the future. Add a PML pan with a drain plug. It holds more fluid and is finned to help with cooling. It’s a messy job and can be a pain in the ass depending how you maneuver the exhaust.
I drain and fill 30k and the next time I do a complete trans service with a filter the next time trans is due.

View attachment 189505 View attachment 189506

I will keep that in mind when I decide what is my best choice. I just want to make sure I make the right choices when it comes to maintance on my Tahoe. Thanks for the help.

 

[RED TAHOE LS]

Brian to the forum from Georgia Dawg country, glad your here. As with anything you will always get mixed opinions . IMO, changing trans/fluid @ 30 k is not necessary with today's updated technology compared to the older vehicles. I definitely would not use a FLUSH MACHINE with someone's old fluid residue in it, as is done today in many QUICK LUBE places. If the fluid is not brownish color or smell like it's burned, leave it be. Good luck.
David g.........

 

[Denali2k8]

Make it easier on yourself for the future. Add a PML pan with a drain plug. It holds more fluid and is finned to help with cooling. It’s a messy job and can be a pain in the ass depending how you maneuver the exhaust.
I drain and fill 30k and the next time I do a complete trans service with a filter the next time trans is due.

View attachment 189505 View attachment 189506

Link to the pan? Coming up on 100k miles myself and unsure of the service to the trans.

 

[Brian750]

I was thinking of doing it this way like he does in this video. He doesn't use a machine. He purchased sum sort of factory cheverlot nipple and unplugged a line near top of motor and attached nipple and hose and would let the trans pump all the fluid out. Add new until it came out of the hose pink. Then filled it up and was done. Seems like a safer bet than using a flush machine. Thoughts???

 

[calif phil]

I drop the pan, change the filter with an AC Delco filter and refill with fluid.

 

[sumo]

Link to the pan? Coming up on 100k miles myself and unsure of the service to the trans.

https://www.yourcovers.com/transpan_9427.php

 

[HiHoeSilver]

I was thinking of doing it this way like he does in this video. He doesn't use a machine. He purchased sum sort of factory cheverlot nipple and unplugged a line near top of motor and attached nipple and hose and would let the trans pump all the fluid out. Add new until it came out of the hose pink. Then filled it up and was done. Seems like a safer bet than using a flush machine. Thoughts???

This is how 'most' of us do it. Use the cooler line to the radiator and a 5 gallon bucket. You can pump out the pan first, so if you're dropping it to change the filter it's empty already.

 

[Doubeleive]

if you have the 6 speed then this pan works I put it on mine very happy with it, even though it was out of stock when I was ordering it for about 3 1/2 months, there in stock now though
http://www.bmracing.com/products/70295-cast-deep-transmission-pan-for-gm-4l80e-transmission/

 

[techbiker]

This is how 'most' of us do it. Use the cooler line to the radiator and a 5 gallon bucket. You can pump out the pan first, so if you're dropping it to change the filter it's empty already.

I only dropped the pan without pumping out once... One of my worst mistakes ever. ATF dumped all over my head and the garage floor! My hair was still greasy after a shower.

 

[KATfishing]

try running a carfax on it if it was serviced at a dealer or national company it may show when it was done last.

I agree! Bought my 08 denali at 80K. Ran carfax and immediately saw that dealer had serviced transmission and other fluids at 65K. Helped to inform my decisions going forward. I'm at 126K and going to have fluid/filter changed by shop. Still under warranty for another 6K, so if something shows up during/after service, at least I have a few thousand mile grace period.

 

[steve45]

I don't believe in changing transmission fluid. If you've waited this long, you'll probably end up with seal problems after they soak a while in new fluid.

I've had a number of transmission failures--NONE of them fluid related. Don't waste your money.

 

[Kendall69]

This may be in wrong section feel free to move....
I have an 08 Tahoe I bought last year in Dec. I keep the oil changed every 3000 miles but I don't know if the trans or diff fluids have ever been changed. It has 144k on it so my question is what does everyone recommend when it comes to trans service. Just filter change and new fluid or new filter, flush and new fluid?

Appreciate any info you all have for me.

For me, I change every fluid on every vehicle I purchase it the day I bring it home - including new ones, bye especially used ones. New ones I won't do the tranny or coolant but front and rear diff's get changes, the engine gets changed, transfer case gets changes. I want the synthetics that I use in my vehicles and never trust what was put in usually it's the cheapest stuff made. So who cares if they did or didn't do it, do it anyway with good synthetic fluids and do it right. Also, change the filter. I have never heard of a vehicle being damaged by too many fluid changes too often.

 

[Big Mama]

My trans guy has a rule. If the trans is giving you trouble change the fluid and filter. If not flush and fill. I’m at 118k and did a flush. There’s a hybrid method of drain and fill then drive and repeat until fluid looks right. I’ve never seen this come out right. A drain only empties the pan not the converter that has the majority of your fluid.

 

[guy from norcal]

I don't believe in changing transmission fluid. If you've waited this long, you'll probably end up with seal problems after they soak a while in new fluid.

I've had a number of transmission failures--NONE of them fluid related. Don't waste your money.

I would rather spend $ 200 on new fluid,filter, and new pan with drain plug, rather than do nothing, And wait till it blows up on you. now your out a few $ thousand.

 

[miatawnt2b]

Youtube Yukon transmission flush on youtube. There is a method of pulling the cooler hose off of the trans cooler and using the transmission's built in pump to flush all the fluid so you can get a 100% change. Basically refill 2l, pump 2l, repeat until fluid runs bright red. Works really well.

 

[GranPrix]

Kinda on topic but for those of you that dropped the pan and used a new gasket, by any chance did you use any RTV on the pan?

 

[Jason_S]

Kinda on topic but for those of you that dropped the pan and used a new gasket, by any chance did you use any RTV on the pan?

Not normally. That being said, I have used dabs of RTV or grease to help hold the gasket in place until I can get the pan in place and a couple of bolts started.

The only time I remember using RTV on the entire gasket was because the gasket surface on the transmission itself had gotten a bit gouged in a couple of spots and we couldn't get the gasket to fully seal. Even then, we only gave the transmission side a very light application.