Automatic Transmission

[HersheyGirl]

I just got rid of a 94 Chevy G-20 van.  My transmission was doing the same thing...hard to shift it to drive or reverse when it was cold.  Took it in to have it looked at, they checked it throughtly, and said that they thought it was a transmission cable and would be very expensive to replace.  They also told me that it does no harm to the transmission, just a pain to wrestle with it when it is cold.  When it warms up, no problem.  I also replaced the transmission a coulple of years ago, Cottman's did it and the cost was about 2700 dollars, it was rebuilt.  They said it cost so much due to it needing a complete rebuild.  I know it was pretty bad and was hardly working.  I had about 150k miles when that was done.  Hope this helps.

[austinado16]

...What happens is that the new fluid cleans all the gum and varnish that remains on the transmission parts and flushes it down into the pan. When this happens it is picked up in to the filter and plugs the filter. After changing the filter and fluid again it works fine.

Wow...excellent info! Hadn't thought of this, but it sure makes perfect sense.  Do you think it's caused by not doing oil/filter changes frequently enough, which might be allowing the transmission to get more nasty inside?

[campdaddy]

I have sold more trans filters and fluid in my 13 years selling parts than I can remember. I have also hear of and experianced a problem after changing filters. What happens is that the new fluid cleans all the gum and varnish that remains on the transmission parts and flushes it down into the pan. When this happens it is picked up in to the filter and plugs the filter. After changing the filter and fluid again it works fine. As far as the type of fluid to use in your vehicle:

Yep, I've also had that happen to a '96 Jimmy I did the fluid/filter thing with. On my Plymouth, I had planned to do a filter change again in the spring just to preclude what you are talking about. I figure another filter and 3-4 qrts of fluid is cheap insurance. Another thing that happened, I forgot about this, is that one of the seals on the side of the transmission began to leak on the Voyager. Not the gasket I had changed, but apparently the new fluid had cleaned old seal also. It seeped out small amounts of fluid. Not enough to see on the dip stick but enough to leave a wet spot on the driveway. About drove myself crazy looking for that. After 4-5 weeks it quit and YES, I did check the fluid to make sure there was still some in there and hadn't all drained out!! LOL I don't know if the new fluid and the old seal finally became compatible or what, but everything is good for now. No leaks, shifts good, and noticeably quieter. I'm happy, but you're right, that is something to look out for.

[WolfPack]

i am going to change the fluid and fliter agan check to make sure there is no shaving in the pan to. my owners manual say to use Dexron 3 is preferred if available if not can use Dexron 2e is acceptable if Dexron 3 is unavailable. the manual say to change every 15,000 miles for the veh under 8,600 GVWR and  12,000 for veh over 8,600 GVWR. AND  if not pulling the a trailer frequent or in hilly or mount terrain than youcan change every 30,000 miles for veh under 8,600 GVWR and every 24,000 miles over 8,600 GVWR. i am going use service at 12,000 miles being its a conversion van with a rised roof which addes some weight to the van and being i drive on some hilly Roads that way i know its being service. i still going to talk to the transmission people to. THANK FOR ALL THE IN PUT ON THIS.

[aw738]

In the time that I have been selling T-fluid I have never sold any Dexron II of any kind. If you can still find it, it has been setting on the shelf for a loooonnnng time. Dexron III should be almost everywhere you look.

[WolfPack]

well i called the transmission shop to day and talked to the mech and told him what the transmission it had done what he told me was the cold temp and that he has seen transmission do that when its realy cold.i also ake about flushing the transmission he didn't have the equipment. so i called the dealer and they told to change the fliter and fliud there might have been some drit that got in to the valve body. thet don't do flushes to they just change the fliter and fliud.

[wavery]

well i called the transmission shop to day and talked to the mech and told him what the transmission it had done what he told me was the cold temp and that he has seen transmission do that when its realy cold.i also ake about flushing the transmission he didn't have the equipment. so i called the dealer and they told to change the fliter and fliud there might have been some drit that got in to the valve body. thet don't do flushes to they just change the fliter and fliud.

I agree 100%. I have seen flushes destroy transmissions on high mileage vehicles. Some shops like to push them because flushes are easy to do by less skilled techs and very high profit. They couldn't care less if it screws up your trans.

When I worked for AutoNations, they put one of those machines in every shop. After about 12 months of having to overhaul screwed up transmissions on used cars that we sold and we did flushes to, we decided to pull them out of all of our shops and go back to traditional transmission services (pulling the pan and changing the filter).

I still say that you would do well to switch to Mobile1 (or some other brand) Synthetic Trans oil. It isn't effected by temperature and it shifts smoother.

The biggest reason for changing trans oil is because it can burn and turn to varnish. Synthetic cannot burn and will never turn to varnish. Petroleum based oil has very poor heat disbursement qualities. Synthetic oil disburses heat at nearly double the rate, making your trans run cooler. Cooler trans = longer life. Chrysler recommends never changing the fluid on vehicles with synthetic trans oil. I would say that you can AT LEAST get double the mileage out of it.
http://www.mobiloil.com/USA-English/MotorOil/Other_Products/Mobil_1_Synthetic_ATF.aspx
http://www.amsoil.com/storefront/atf.aspx

I run synthetic oil in all my engines and transmissions. I even run it in my Honda Generator and my 8hp Subaru gas pressure washer.

[WolfPack]

wavery you are right 100% my van is due for an oil change so get the mobile 1 synthetic at wal-mart i think its on sale for 21.00 for 5 q thats not bad and by the end of the month it will be time to change the trans fliud and fliter. get this done thin i can work on fixing my engine in dodge doakota. thanks for the info and the web address on mobile 1 and amsoil
                                                          James

[austinado16]

I agree 100%. I have seen flushes destroy transmissions on high mileage vehicles...

Great info Wayne.  I've always felt the same way, but never really had any concrete info to back up my fear.

I don't have synthetic in the Suburban trans yet, but I will convert it at the next trans service I do.  I've got a mechanical temp gauge so it'll be interesting to see how it responds.  I'm running Motul Synthetic in the Audi Quattro's trans.

[flyfisherman]

O.K. ... I have a question for the west coast transmission genius ...

Suppose I was to go for the 100% synthetic route, would you do the standard fluid and filter change or look for a shop that does the total transmission flush?



Fly

[wavery]

O.K. ... I have a question for the west coast transmission genius ...

Suppose I was to go for the 100% synthetic route, would you do the standard fluid and filter change or look for a shop that does the total transmission flush?



Fly

I'm not sure who you are referring to but it can't be me because I'm certainly no "Genius". However, I will give you my $.02 worth.

I think that "Flushing machines" do more harm than good (JMHO). I also think that you might find it difficult to find a shop that has a flush machine loaded with synthetic ATF. If they tell you that they do, I wouldn't trust them (but that's just me).

I can only tell you how I made the transition. I pulled the pan, replaced the filter and refilled the trans with about 3 qts of synthetic ATF. Then I pulled the lower transmission cooler line off of the radiator and attached a piece of hose to the line and another one to the radiator and ran them to a one gallon container. I started the engine and let the container fill with oil while I poured an additional gallon in the fill tube, then turned off the engine. I then topped up the trans with synthetic oil. The entire process took 11 qts of synthetic ATF (on my '99 Chevy S-10).
http://www.amsoil.com/lit/EASY%20STEPS%20IN%20CHANGING%20ATF%20FLUID2.pdf

One tip:
When you unbolt the pan, loosen all the bolts on the pan about 6 turns. As you loosen the bolts you may have some oil start to come out. Try to direct the oil to one corner and remove the bolts in that corner and slowly lower the pan after spilling enough fluid into a large drain pan, to do it comfortably.

It doesn't hurt to mix petrol ATF with synthetic ATF though. Although, if you have a pre-'99 Chrysler product, they recommend removing all Petrol ATF as their transmission have been found to work much better with the synthetic.

[flyfisherman]

I'm not sure who you are referring to but it can't be me because I'm certainly no "Genius". However, I will give you my $.02 worth.

I think that "Flushing machines" do more harm than good (JMHO). I also think that you might find it difficult to find a shop that has a flush machine loaded with synthetic ATF. If they tell you that they do, I wouldn't trust them (but that's just me).

Well, you'll do until one comes along!

With my previous TV, a '00 GMC Sonoma, I did have a complete flush job on it. Since I've tried to change tranny fluids & filters every 25,000 on my towing vehicles, did the total flush job on the 50,000 mile mark. I was on the road on a fishing trip in northern Michigan and the Chevy dealer I stopped off at for an oil change was featuring the total flush and they were saying how much better it was for the vehicle. A regular tranny fluid and filter change cost close to a $100.00, the total flush price was something like 150.00 -  I've since sold the little truck to a friend and it's now close to 200,000 miles and the tranny is still going strong!

My GM dealer here does not do the total flush and says they're a waste of money. I'm curious as to why you say they do more harm than good (I have no idea is the reason I ask). Have thought about doing the synthetic fluid in that heat factor is reason eneough. Here, I'd have to have someone change it out for me and finding someone who would do as you oulined and remove all the old regular fluid.



Fly

[wavery]

My GM dealer here does not do the total flush and says they're a waste of money. I'm curious as to why you say they do more harm than good (I have no idea is the reason I ask). Have thought about doing the synthetic fluid in that heat factor is reason eneough. Here, I'd have to have someone change it out for me and finding someone who would do as you oulined and remove all the old regular fluid.



Fly

All transmissions have little hidy-holes where dirt, metal shavings & varnish tend to sit. When the power flush is done, it tends to disturb some (or all) of this debris, especially on ill-maintained transmissions. On a regular oil & filter change, the pan must be cleaned of debris so that it is not picked up from the increased circulation from the new filter. With the power-flush, this material is then circulated through the valve-body that has some extremely small oil channels, pistons and valves that can get fowled by this debris. That's the reason that the transmission has a filter in the 1st place.

Most (but not all) of the debris is caught by the trans filter during the power flush but the problem is, they don't change that filter. The filter will then become sluggish and cut down on oil circulation. Over time, that filter may become 100% plugged and stop oil circulation and maybe even come apart and plug up the valve-body and other vital parts.

If you ask the people that are selling the flush, they will tell you that the trans filter really isn't a filter at all and is really just a screen that is designed to catch large pieces of debris. That is NOT true on most vehicles.

Now, having said all that, the flush may be a good thing if it is done from the 1st service at 25K miles and done regularly. I would still recommend changing the filter after every other flush is done (especially the 1st one). The problem is, most people don't service their transmissions until they start having problems. The 1st service is often around 75-100K miles and that is not time to do a flush.

The power flush is much less labor intensive, it can be done by un-skilled techs and there is very little cost to the shop and they actually charge MORE (in some cases). All they have to do is disconnect one cooler line and put the flush machine in that line. This takes about 15 minutes. A regular service takes about 1+ hour, as the tech must unbolt the entire trans pan (about 12 bolts), pull out the old filter, clean the pan, replace the pan gskt, install the new filter, re-bolt and torque the pan then re-fill the trans fluid. The profits are tremendous with the power-flush and their is no recourse against the shop if your trans fails after the service (it can never be proved that it was due to the flush).

Last but not least........when the flush is done, you do not get new ATF. What you are getting is ATF that has been super filtered from the car that was serviced before yours. However, it isn't new. This is one of the reasons that I say that I wouldn't trust anyone that might tell you that they have a flush machine with synthetic oil. The truth is, they really don't know what came out of the last guys trans but it probably wasn't synthetic.

[austinado16]

Just talked to my brother who's a service writer in a local indy shop.

Their machine plumbs into the cooler lines and they run about 16qts of brand new Valvoline Max Life semi-synthetic through.  They do not put someone's old fluid back in.  $180 for the service.  If you want the pan removed, cleaned and filter replaced, it's an additional $135.

He says they've never once had a transmission have problems after a flush service.

When I worked at the local BMW/Nissan dealer our machine only put in fresh.  It did not "recycle."

I'm still not really hip to the flush treatment, but at least I know more about it.

[WolfPack]

Thats lot of money the dealer said to change the fliter and fliud again and see how it does so next pd i wll change it again.