tranny oil change?

[rickheide]

i just wanted to know anyones opinion on whether to change the oil on my 97 5.7 silverado. it has a pretty dark color to it, but i've been told by many that after they changed the oil the tranny begane to slip. any info will help.

[LT-Z71drvr]

I would, but just make sure it is flushed.
If you dont have it flushed, it aint worth it.

[broughy84]

Flush it!

[sitdusa]

Yeah flush it!

[tom3]

Similar deal on our S10. Decided to risk it and changed filter and refilled with Valvoline Max Life ATF. Glad to see the pan was pretty clean, no material in the bottom. Trans works fine now and I assume it will be fine for many miles.

[djmoore85]

would definitely do a complete flush, not those cheap 3/4 drain and new pan filter+gasket deals a lot of shops do. if u do decide to change the fluid, see and watch for yourself that it is a COMPLETE flush. i hav friends that got the cheap version and it just did nasty damage to the tranny.

[wafrederick]

Do not do a flush!It is a big no no.My father knows a guy that owns his own transmission shop that cleans valve bodies and makes money that way because someone had their transmission flushed.The lines are above the filter and where does the dirt go?The dirt goes into the crevises of the valve bodies causing shifting problems.My father has one coming for a transmission replacement,transmission was flushed,causing a rattle and was 4 quarts low.It is now burned up and transmission is going to be replaced.The best thing to do is replace the trans fluid and filter.

[sreve]

Originally Posted by wafrederick

Do not do a flush!It is a big no no.My father knows a guy that owns his own transmission shop that cleans valve bodies and makes money that way because someone had their transmission flushed.The lines are above the filter and where does the dirt go?The dirt goes into the crevises of the valve bodies causing shifting problems.My father has one coming for a transmission replacement,transmission was flushed,causing a rattle and was 4 quarts low.It is now burned up and transmission is going to be replaced.The best thing to do is replace the trans fluid and filter.

a flush machine hooks up to the trans cooler lines. fluid coming out of the trans (dirty) is dumped and replaced by new fluild.dirt is not an issue.
gm torque converters have no drain, pulling the pan does not change very much fluid 5qt on a 4L60e it holds 11qt total. filter condition is obvious by the rate of the fluid exchange. another myth is : you will not over or under fill a trans with a flush machine you end up with exactly what you started with . if it was a qt low to start it will be a qt low when you finish regardless of the amount of fluid you run through it.gm trannies usally slip there azz off 2qts low and driving one in this condition means he did it to himself.

[corning_d3]

Yeah, flushing the right way is beneficial to longer transmission life.

[MT-2500]

Well here is my 2 cents on the deal.
People that tell you never to change it are full of crap.
So look at it this way if you do not change oil and filter it is going to go for sure.
What happens when you do not change your engine oil and filter?
Get the picture?
Most people just wait to late to change filter and fluid.
But late is better than never. Go for it.
Is your trans acting up or what made you think about servicing it?
How many miles are on it?
Has it ever beed serviced?
Any check engine lights blinking at you?
MT

[xclodbuster]

Never, ever flush a trans. There is no "safe" way to flush a trans unless you own the flush machine and control it yourself.

Flushing a trans has several pitfalls...

The most obviuos is that the last vehicle hooked up to that flushing machine probably was on it's last leg and was generating tons of debris. Most owners, when the trans starts to act up, rush to get a "flush" in the fervent hope that it will cure the problem. So....flush machines, by definition, see the worst of the worst. If the lines aren't cleaned, hooked up improperly, oil is reused or recycled, etc....then you are screwed as your trans gets the dose of debris from the last trans. No matter how good the intentions of the shop, one simple mistake and your trans gets the debris.

Flushing is supposed to negate the need for removing the pan, cleaning the debris and replacing the filter.....BS. There is considerable debris coating the inside of the trans pan with miles as anyone who has done this can attest. That is part of the maintenance, removing the pan, cleaning the screens and replacing the filter and cleaning the pan.

All that debris in the pan is laying around in areas where there is little oil flow by definition...it tends to settle in the areas where the oil is quiet and just lies there not hurting anything....until the "flush" stirs it up and circulates it thru the trans. What a concept....LOL

Reverse flush.....?????.....what logic makes anyone think that it is a good idea to reverse the oil flow path in a reverse flush and flush sediment and debris into areas that are normally protected by filters, etc...???? Stupid idea. Period. No other way to describe it.

"Transmission flush" machines are money makers for the shops and dealerships because they are quick and easy and they can actually charge more money for it under the guise of it being "better" for the trans....when it is really a detriment....suckers born every day......

Read the factory service manuals and point out the place where a transmission "flush" is recommended.

So what if all the oil cannot be removed. A "flush" doesn't remove it all either.


If you really really want to replace as much oil as possible in the trans, drain the pan, service it by removing/cleaning/changing the filter and reassemble. Refill the trans with fresh fluid. Disconnect one of the cooler lines at the radiator, put it into a bucket and start the engine. Let the trans oil pump purge the old oil into the bucket so that nothing is subjected to abnormal oil flow. Start pouring oil into the trans to keep it full while the idling engine/trans oil pump purges the fluid thru the system. Easy and quick and gets ALL the fluid out....and eliminates any risk of hooking up to a "flush machine".

Guys....FORGET THE IDEA OF FLUSHING YOUR TRANSMISSIONS. Normal trans maintenance is a good idea. Drop the bottom pan, change the filter and clean everything up and refill the trans with fresh fluid. Do the cooler line/bucket purge if you are really fastidious about changing all the fluid.....but....DO NOT hook your trans up to a flush machine.

Really now, would you get a blood transfusion from an unknown source that is reusing needles......about the same thing if you think about it. A flush will do absolutly nothing more than a good drain and refill will accomplish...and potentially a lot of harm. Do not take the risk. Just because some have had good experiences (or the lack of a bad experience) with a flush does NOT mean that they will always go good.

2 cents... ok, 4

[MT-2500]

Welcome to AF.
I see this is your first post.

A Quote from your post.
If you really really want to replace as much oil as possible in the trans, drain the pan, service it by removing/cleaning/changing the filter and reassemble. Refill the trans with fresh fluid. Disconnect one of the cooler lines at the radiator, put it into a bucket and start the engine. Let the trans oil pump purge the old oil into the bucket so that nothing is subjected to abnormal oil flow. Start pouring oil into the trans to keep it full while the idling engine/trans oil pump purges the fluid thru the system. Easy and quick and gets ALL the fluid out....and eliminates any risk of hooking up to a "flush machine".

If you do that ,that is a flush. May not be a machine flush but it is a flush.

You have some good ideas but there is times that a total fluid change/flush is needed.
Like a newer ford with the mercon fluid that has died as low as 25-35k.
Only way to fix it is a total flush or fluid change.
Flushing is not a bad deal on in most trans.
But sometimes the way it is done is much of the problem.
Not changing the filter and putting in additives or the wrong type of fluid.
Or setting the flush machine wrong.
Or people wait untill the trans is on last leg and think a flush will cure all aligments.
Always change the filter with a trans service and do it on a regular mileage basic,not ever 150-200k.
MT

[sub006]

I have 385,000 miles on my '90 Suburban (original owner) and just had my third 700R4 installed.

Got 225,000 on my last one from my trusted trans shop. They put in thinner multi-disc clutch packs on 2nd and 3rd, added a cooler same size as my Chevy's factory tow package engine oil cooler, etc. Serviced it once a year (30,000 miles), pan off, filter change, 6 qts fresh conventional ATF.

At about 100,000 miles it began to act like the OE trans when that one was failing. Disconnected one of the cooler lines and ran at idle 'til the line gasped that it was empty. Refilled with Mobil 1 synthetic ATF and got over 100,000 additional miles with like-new performance.

When this unit slow-motion grenaded at 225,000 trans miles, source of shrapnel was diagnosed as a bearing coming apart.

From my BMW Club tech resources, I learned this is a common problem. Conventional and synthetic ATF is designed to interface with clutches and valves; lubrication of bearings is secondary, a compromise at best.

BMW independent techs and mechanics recommended Red Line D4 ATF, a synthetic that is certified to meet GL-5 OIL lubrication specs. Dick Guldstrand, the guy who does the suspension work on my Corvette, confirmed that D4 is standard fill on automatic-equipped versions of the $150,000 new 427 small-block 'Vettes he builds.

So I fill my new trannys with D4 (about $9 a quart, 10% off on case of 12). I think an almost-complete fluid change as described above, less torque converter (not a flush) might be a good idea at the third or fourth 30,000-mile service.

My trans techs have switched back to thick single disc clutches, but with a new facing material. To firm up the shifts a bit, they installed a new Corvette servo. I'm shooting for 300,000 miles on my latest 700R4!

If you want to drive well into six-figure miles, forget the owners' manual recommendations. GM wants to have a low published maintenance cost and only needs the vehicle to get to the end of the warranty, or about 100,000 miles at most, so they can sell you a new one.

If you want LONG and TROUBLE-FREE truck life, it's a continuous learning curve. Read magazines and forums like this to get ideas on new products, modifications, "little tricks" etc. But DON'T jump into using a new idea right away. Cultivate relationships (spend some money) with top independent fleet mechanics, techs and race shops. When all three categories agree on something, it's probably a winner.

[Ob-1]

A few years ago we put a plow on the truck and that forced me to better maintain the transmission. One trick that works for us is to put in a drain plug in the pan and change out the fluid every time the oil is changed. This has been very effective. We have never had any transmission problems at all with 105,000 miles and plowing over 100 driveways a storm. I also installed a cooler and a transmission temperature gage to monitor it as best as possible.

HTH,
Bruce

[cbongo247]

new filter and flush it. please.