Transmission fluid change

[Deano]

The transmission is coming due for a fluid change on my 2004 Chevy 3500 Van based RT 210 Pop.
Has anyone changed over to synthetic fluid?
Any issues or problems?

[booster]

Originally Posted by Deano

The transmission is coming due for a fluid change on my 2004 Chevy 3500 Van based RT 210 Pop.
Has anyone changed over to synthetic fluid?
Any issues or problems?

I think almost everyone who has done a fluid change lately has moved to the Dexron VI fluid. It is much better stuff, especially for high temps that a lot of us see in the class b's.

The only major issue is getting all the old out to get a complete changeover. Draining the pan, and the cooler will not get even 1/2 out, so it will take several changes to get most changed. Best is to find somone who has their trans flush system setup with Dexron VI. You may only find that at a Chevy dealer. It is always a good idea to put a drain in the pan when you do a change to make the next one easier.

Many, maybe most, of the independents have their flushing systems setup with "universal" fluid which is allegedly good for Dex VI, Honda, Toyota, etc etc all the way up to space shuttles. Personally, I consider trans fluid about the only fluid that I totally agree is needed to meet the actual manufacturer spec, like Dex VI, the specific Honda fluid, etc. The fluids and transmissions are designed together to get the right stick/slip, actuator timing, etc, so it is important to be the same.

I use Valvoline Dexron VI rated fluid which is GM spec tested. The Valvoline universal fluid has not passed the Dexron VI testing and been approved. Other good brands like Amsoil, Redline, Royal Purple, etc have trans oils they "recommend" for use in Dexron VI applications, but they are also have not been tested or approved. They may be fine, they may not be, and just because the say they have warranty doesn't mean they have ever payed one because you can't prove it was the oil that caused the problems.

When I changed over my 1996 Buick Roadmaster with a 4L60E trans,the couple of tiny leaks I had got a bit more, so I had to fix them. Shift rod seal and a cooler line crimp connection.

[pearll]

Draining only captures a certain percentage of total fluid, not sure of amount. One method I have read is that instead of a transmission flush is to drain and fill, drive 5 miles and repeat 3-4 times. That way you are able to more or less completely change all the fluid.

[JohnnyFry]

That sounds like a pretty expensive way to change out the fluid...not to say wasteful.

[booster]

Originally Posted by JohnnyFry

That sounds like a pretty expensive way to change out the fluid...not to say wasteful.

I agree, but there are few good options if you want to get the benefits of the Dexron VI fluid.

The flushing machines will completely change the fluid, but it is hard to find an independent shop that uses Dexron VI and not the universal fluids in their flushing machines. I was not able to to find anyone but the GM dealers who used Dexron VI in their machines, and they are also in the "not inexpensive" category.

I think if I wanted to do a 4L80e like we have in our vans, and make sure I got Dexron VI and completely changed, the dealer may well be best source, especially if you watch for a sale on trans service, which happens fairly regularly around here. The 4L80e uses an in the pan filter, rather than the more modern screen at the valve body, so it does also need to be changed fairly regularly, and would be with a full flush service at the dealer most places.

[Bruceper]

Don't do a flush from an oil change type of shop. If you want a flush go to a transmission shop.

An oil change shop will likely not cover you if they mess up. A transmission shop will cover you.

[booster]

Originally Posted by Bruceper

Don't do a flush from an oil change type of shop. If you want a flush go to a transmission shop.

An oil change shop will likely not cover you if they mess up. A transmission shop will cover you.

Have you been able to find any in your area that use the Dexron VI in their machines? Unless things have changed in the last few years, rare around here.

As always, the disclaimer on a full machine flush is that if the trans is old and hasn't been maintained, a flush can kill it by breaking loose debris and plugging passages. For those times, best to do nothing or change just the pan fluid until it cleans up.

[pearll]

That is my understanding also. Maybe a drain transmission oil change every 7k miles which will completely change fluid by the 30K miles. The thought is that a transmission flush at a shop is just not that good for transmission. Maybe it really depends on age of transmission.

[JohnnyFry]

Why is an trans flush not good for the transmission? Exactly how is it done? What downside is there to removing the pan and doing it that way?

Thanks

[booster]

To figure how long it takes to change it all (almost, as you will never get to 100%) take the % that gets changed off of how much old is still left.

So if you get 40% of the fluid out, you have 60% old left. Next change will remove 40% of the 60 percent or 24% so 36% left. Next removes 40% of the 36% or 14.4% so 21.6% left. etc, etc, etc.

Some trans will slowly drain some of the torque convert fluid that is trapped in it, once the pan is drained or removed, but it does take a while. I have seen .5-1 quart more come out overnight on some transmissions, so if you are doing a changeover and have the time to let it sit in a clean spot, it can be worth the wait.

[InterBlog]

I had this done a few weeks ago on our Sprinter-based Class B for the reason as stated - it was explained to me that it was extremely difficult for a DIYer to do a thorough job, and the explanation sounded credible (rather than sounding like a sales pitch). I had it done at our local Mercedes Benz Sprinter shop, so needless to say, it wasn't cheap. If there does come a DIY approach in which I develop confidence, I might attempt it the next time, but thankfully it's a task that doesn't have to be done very often.

[booster]

Originally Posted by JohnnyFry

Why is an trans flush not good for the transmission? Exactly how is it done? What downside is there to removing the pan and doing it that way?

Thanks

For a complete flush, they hook up a big tank of fluid to the cooler lines and constantly feed in clean fluid as the old is bled out. They keep it up until the fluid comes out clean. The engine is running during it all so the torque converter and all the passages get flushed out too. The problem comes from having the detergent value of all clean fluid in the transmission which can attack buildup and have it break loose and go bad places. Some even say that just changing what is in the pan is too much also, but it certainly would be better than all of it. Many will also just say leave it dirty, as there is less risk.

Downside of removing the pan is that you don't get all the fluid out, usually 1/2 or less. Some DIY folks have been known to do the pan removal in a dirty area, also, and cleanliness counts in transmissions.

[pearll]

Well that is a good explanation. I thought is was because of the trans flush machine. It would make sense that the cleaning power of all the new fluid might not be good for a old transmission.

[Porsche911]

Originally Posted by InterBlog

I had this done a few weeks ago on our Sprinter-based Class B for the reason as stated - it was explained to me that it was extremely difficult for a DIYer to do a thorough job, and the explanation sounded credible (rather than sounding like a sales pitch). I had it done at our local Mercedes Benz Sprinter shop, so needless to say, it wasn't cheap. If there does come a DIY approach in which I develop confidence, I might attempt it the next time, but thankfully it's a task that doesn't have to be done very often.

What is the time period/miles for MB transmission service (we have a sealed transmission on our MB 2007 Sprinter Chassis) and what did your MB shop charge you for the service ?
Thanks in advance

[BBQ]

.

You know the saying... If it ain't broke...

[Porsche911]

SO BBQ are you saying it never needs service?

[BBQ]

Originally Posted by Porsche911

SO BBQ are you saying it never needs service?

IDK... I have never driven a car long/far enough to need transmission service.

[booster]

Originally Posted by BBQ

IDK... I have never driven a car long/far enough to need transmission service.

And I have never had one a short enough time not to need repeated maintenance!

[InterBlog]

Originally Posted by Porsche911

What is the time period/miles for MB transmission service (we have a sealed transmission on our MB 2007 Sprinter Chassis) and what did your MB shop charge you for the service ?
Thanks in advance

Excellent question. The 2006 Sprinter service manual reads "once only at 80,000 miles" for transmission servicing. However, the local MB Sprinter shop vehemently disagrees with that recommendation and in fact their paperwork that they gave to me cites a 40,000-mile interval explicitly. What might have happened is that, given that Sprinters were re-plated as Dodge and Freighliner in those earlier years, the recommendation was changed, or believed as needing to be changed, but the information never got disseminated formally.

My transmission fluid was changed at 45,000 miles because it already showed evidence of degradation ("burned") and it had debris in it.

Now, if your Sprinter is a 2007, it's probably an NCV3 rather than a T1N. The recommendations and realities may vary.

I say "probably" because sometimes people cite their MH production year and assume it's also their chassis year. 2006 was the last year in which T1N Sprinters were produced, but the resulting motorhomes / Class Bs are often dated as 2007 models.

In answer to your other question, we have a dedicated Sprinter-only servicing shop, not just a generic MB service shop, in our area. I've gotten to know those folks and I trust them. They charged me just shy of five hundred painful dollars to do the transmission servicing.

[BBQ]

.

The new Subaru have sealed transmission case as well.
Maybe that's the way to avoid contamination?