Trans fluid gasket filter pan

I was wondering if you guys had some input on what I am about to do? I am going to drop the pan, drain the fluid, change the filter, new gasket, refil with tranny fluid. Should I refill with the same regular tranny fluid or can I refill with synthetic and have both synthetic and non synthetic in the tranny? I know it is ok to do wil oil just wanted to make sure it was ok with tranny fluid. If it is ok what kind of results should I expect from someone who has done it or who has had a flush and refilled with synthetic? Thanks guys

Before you do that I would have the transmission fluid completely replaced with one of those machines that hook up to the transmission cooler lines.

Before you do that I would have the transmission fluid completely replaced with one of those machines that hook up to the transmission cooler lines.

I did the flush last year. The place that did it said my tranny fluid looked good then and I had owned the truck for 35k at that point and had not had it done and I have no clue when the woman before I had it did it. So I had it flushed last year and everything was ok. think I still need to get it flushed?

No, just replace the filter and use normal ATF to top it up.

No sense using only a little bit of synthetic.

No, just replace the filter and use normal ATF to top it up.

No sense using only a little bit of synthetic.

I hear yea. About how much transmission fluid is lost when you drop the pan and swap out the filter?

About 4 Quarts or so......
Get ready to take a HOT bath in transmission fluid my friend...
Been there, done that................................
:lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol:

I don't think it will be a full 5 qts with just the pan drop. I may be wrong.

loosen the pan bolts and loosen one corner more than the other four.

That way you can place a pan under that corner and collect what you drain.

I don't think it will be a full 5 qts with just the pan drop. I may be wrong.

loosen the pan bolts and loosen one corner more than the other four.

That way you can place a pan under that corner and collect what you drain.

I hear yea on the tranny bath! I learned that the hard way on a grand prix I used to own, but since then I do it the way BlazerLT suggested, just loosen it enough to let it pour out one corner. I can't remember how mych fluid a friends blazer took when we did it so that is why I asked about how much was lost.

Make sure you clean the pan of all old gasket meterial , carefully install a new O ring and filter, and don't overtighten the bolts, yada yada yada. Your trans will thank you later.

:rofl::rofl::rofl::rofl::rofl::rofl:

Make sure you clean the pan of all old gasket meterial , carefully install a new O ring and filter, and don't overtighten the bolts, yada yada yada. Your trans will thank you later.

:rofl::rofl::rofl::rofl::rofl::rofl:

I know a lot of people who over tighten things and have no idea that is where some of there problems caome from, fools

Make sure you clean the pan of all old gasket meterial , carefully install a new O ring and filter, and don't overtighten the bolts, yada yada yada. Your trans will thank you later.

:rofl::rofl::rofl::rofl::rofl::rofl:
what should the ft/lbs of torque be on the tranny pan?

8 - 10

8 - 10

Are you for real or did you pull that out of your ass? ;)
I am sure you are right I just wasn't that question or answer to pop up! haha

Are you for real or did you pull that out of your ass? ;)
I am sure you are right I just wasn't that question or answer to pop up! haha

ATSG manual says 9 ft-lbs torque to be exact.

I replaced my valve body on my 97 (4L60-E transmission) and refilled 4 qts. I had 5 qts on hand, just in case.

Tip = when retorquing the pan bolts, be very careful on the front middle bolts. It is tough to get those bolts threaded in properly because there is not much clearance between the pan and the cross member. Be sure to thread the bolt in to the case carefully to avoid cross threading the case. If you feel too much resistance, stop and back the bolt out and try again.

Are you for real or did you pull that out of your ass? ;)
I am sure you are right I just wasn't that question or answer to pop up! haha
I got it from the Haynes manual. The haynes manual isn't always right, but I knew that the spec was pretty close to what I've seen before.

Before you do that I would have the transmission fluid completely replaced with one of those machines that hook up to the transmission cooler lines.


Have you switched sides again? I thought you were against the flush last time this came up. Just checking to see if you came across any new info on the subject..

Have you switched sides again? I thought you were against the flush last time this came up. Just checking to see if you came across any new info on the subject..

I am not against having the tranny fluid changed. You can have a flush which is when they add a bunch of chemical in through the system first before they install the new fluid.

I have done some research and dropping the pan doesn't change too much of the fluid.

I do remember BlazerLT saying he was against it. But there are two different flushes out there. There is the lets force new tranny fluid in until it comes out clean and then tighten everything down and send you on your way. Then there is the one I believe BlazerLT is talking about, which is what I had done. They force out all the old nasty tranny fluid with a flush chemical, then they refill everything with brand new tranny fluid, conditioners and some other chemicals. The normal "purge" is about $80 here in Mass. The chemical flush with all the additives is usually around $120.

I do remember BlazerLT saying he was against it. But there are two different flushes out there. There is the lets force new tranny fluid in until it comes out clean and then tighten everything down and send you on your way. Then there is the one I believe BlazerLT is talking about, which is what I had done. They force out all the old nasty tranny fluid with a flush chemical, then they refill everything with brand new tranny fluid, conditioners and some other chemicals. The normal "purge" is about $80 here in Mass. The chemical flush with all the additives is usually around $120.


Thanks for the correction. I wasn't aware of the other option.

Yea, just get the purge with no chemicals introduced.

Fluid swap only.

While we're o the subject again... Has anyone found a good way to do this at home??? I want to run syn but not pay the shops outrageous price!!

from the Auto-Rx website ...

drop pan, change filter, reinstall.

Disconnect BOTH ATF cooler lines at radiator and place a container or pan under each line end (helps to have an assistant). Start engine, shut down after 1 or 2 quarts have come out one of the lines. Refill exact amount of fresh fluid in transmission (this keeps air out of the system).

Start engine again and repeat until clean fluid is coming out of cooler line. This is messy and time consuming but will purge all old ATF from transmission and torque converter. Reinstall cooler lines and start car, cycle through gears, place in park and check level per owners manual. Check for leaks. Top up as necessary after driving and heated up. Don't overfill.



While we're o the subject again... Has anyone found a good way to do this at home??? I want to run syn but not pay the shops outrageous price!!

from the Auto-Rx website ...

drop pan, change filter, reinstall.

Disconnect BOTH ATF cooler lines at radiator and place a container or pan under each line end (helps to have an assistant). Start engine, shut down after 1 or 2 quarts have come out one of the lines. Refill exact amount of fresh fluid in transmission (this keeps air out of the system).

Start engine again and repeat until clean fluid is coming out of cooler line. This is messy and time consuming but will purge all old ATF from transmission and torque converter. Reinstall cooler lines and start car, cycle through gears, place in park and check level per owners manual. Check for leaks. Top up as necessary after driving and heated up. Don't overfill.

Sounds easy enough. Has anyone donee this w/their Blazer? Are the lines easily reached - I've never looked for them. Also, won't flushing after the filter change fill-up the new filter? On the air issue - won't leaving both lines open introduce air in the system?

Boy am I full of questions!!!!

Sounds easy enough. Has anyone donee this w/their Blazer? Are the lines easily reached - I've never looked for them. Also, won't flushing after the filter change fill-up the new filter? On the air issue - won't leaving both lines open introduce air in the system?

Boy am I full of questions!!!!

Sounds horrible!!! I am not sure if I would ever attempt such a messy project. If I really wanted to flush the tranny, it would be worth it to pay the $80 or $120 instead of doing this ATF cooler dribble purge flush. As long as you change the fluid and filter per the chevy recommended intervals, I do not see why you would ever want to flush your transmission anyways. Is synthetic that much better than dexron 3 or something? My truck shifts like butter as it is.

Sounds horrible!!! I am not sure if I would ever attempt such a messy project. If I really wanted to flush the tranny, it would be worth it to pay the $80 or $120 instead of doing this ATF cooler dribble purge flush. As long as you change the fluid and filter per the chevy recommended intervals, I do not see why you would ever want to flush your transmission anyways. Is synthetic that much better than dexron 3 or something? My truck shifts like butter as it is.

Here's the thing... My truck has 90k on it and I am the 3rd owner. I know that the fluid has never been changed and that worries me. I need this truck to last for the next 4yrs and I drive a lot of miles - 30K+ a year. My view on any of my vehicles is to do the best I can for them since I need them to always be ready when I need them. I'm hoping that switching over all fluids to syn will give me better life on the parts and maybe a little help on the gas mileage. Even 1-2 mpg's will help over time.