Montana transmissions

Just wanted to post a message for you all. My 2001 Pontiac Montana van had 50,000 miles on it when the tranny started acting up, dealer did a tranny flush and it ran great for about 5,000 miles then tranny went way south. Dealer wanted $2,500.00 for new one installed, I found a used one with 18,000 miles on it and installed it myself. Installing this was a @#$%. Would not attempt it again. Waiting for (holding my breath) to hear back from general motors on this issue. Transmission shop said to never flush a tranny, thats what made mine go out. They said to only change the filter and fluid. Hope this helps someone out there.

Oh freakin' great.

I have a 2001 Montana with 50K miles on it, and just dumped the warranty.

Thanks for the warning; at least I have all the factory manuals.

Dan

Well to update you all G.M. did respond to my email and said that since I was not the first owner they really couldn't help me with this matter and that they were sorry. (computer generated?) I thought this would be their response anyways. I just wont buy another G.M. again. Good luck to anyone dealing with G.M. too.

There is a service bulliten on GM transmissions for a bad thrust bearing from Torrington.

Tell the dealer to look up the service bulliten. It will likely be the same problem you are having.

No way about the fluid change. You did the best thing for it by keeping the fluid changed. I'm sure it would have failed sooner without the fluid change.

I dont think it matters if you were the first owner or not. With the service bulliten, GM should repair it, or at least pay for most of the cost.

Good luck.
Dan strong

I have to disagree about the fluid change. Unless you`re changing the fluid regularly, when you have high miles on your transmission the rule is not to flush the system. If the fluid is low, add fluid, but never change it. There`s a reason for this.

Over time, friction material from your clutches and bands will wear off. This stuff is still floating around in the old fluid and will still help apply the bands and clutches. When you flush the old ATF, you lose all the old friction material. I always hear about people that flushed their trannies at 90-100k, only to have it fail shortly thereafter.

If you buy a car new, or have a tranny rebuild, I`d recommend changing the fluid every 10k or so. If you don`t, then don`t change it at all. Just drive it until it fails.

I have a `98 Montana with 151k on it and my tranny`s still going strong.

I dont mind changing the filter and fluid, was told that I shouldn't ever had the tranny flushed. G.M. never said anything about a service bulliten.(no suprise there?) Thank you all for the help.

thought i'd share my experience.

our 2000 van with 3.4 l engine occasionally "thumps" into each gear. this is totally intermittent and does not appear to be associated with anything.

i changed the fluid and filter twice within 100 miles, the second time i also added some trans conditioner. since then, (about 20,000 miles) the problem has not occured near as often, but i won't be surprised when i get the call from my wife that "the van won't go".

berto

thought i'd share my experience.

our 2000 van with 3.4 l engine occasionally "thumps" into each gear. this is totally intermittent and does not appear to be associated with anything.

i changed the fluid and filter twice within 100 miles, the second time i also added some trans conditioner. since then, (about 20,000 miles) the problem has not occured near as often, but i won't be surprised when i get the call from my wife that "the van won't go".

berto

I just bought a 2000Montana with 75K on it.

No knowing what kind of maintenance has been done what should I do? Flush or no? What is the difference b/t a flush and just changing the fluid and filter?

Any advice would be great.

If your AT pan does not have a drain plug (the GM 4T65E does not), you can buy a cheap hand pump / dipstick pump. Pump out a few qts of ATF thru the dipstick tube, add fresh ATF in the amount you took out & repeat if you want to clean it up more. You should ATLEAST do this every year or every 20K mi on these trannies if you want them to last. Drop the pan & change the filter every 40Kmi or so.
G/luck
Joel

I just bought a 2000Montana with 75K on it.

No knowing what kind of maintenance has been done what should I do? Flush or no? What is the difference b/t a flush and just changing the fluid and filter?

Any advice would be great.

vanrunner,

i strongly recommend dropping the trans pan and changing all of the fluid and filter right away. it's not difficult so you can do it yourself. my van had 80k on it when i got it and changed the fluid...the fluid was black black black and the filter looked terrible!

I think replacing the filter and fluid is the best thing to do. I would not have it flushed (been there, done that) unless you want to replace the tranny. The filter and 12 quarts of fluid are cheap.

I have a 2002 Pontiac Montana with just over 50,000 miles that the transmission died with no warning. Its now having to be rebuilt at my expence beause the warranty expired at 36000 miles. I have owned over 10 Chrysler mini-vans over the past years with no problem and decided to give GM a chance, poor decision, it will not happen again. Is there any recourse that I might have with GM.

thought i'd share my experience.

our 2000 van with 3.4 l engine occasionally "thumps" into each gear. this is totally intermittent and does not appear to be associated with anything.

i changed the fluid and filter twice within 100 miles, the second time i also added some trans conditioner. since then, (about 20,000 miles) the problem has not occured near as often, but i won't be surprised when i get the call from my wife that "the van won't go".

berto


Many 4t65e's had problems with the pressure control solenoid. It would usally cause harsh shifts intermittently. Sets code P1811. Thought this might help.

Just wanted to post a message for you all. My 2001 Pontiac Montana van had 50,000 miles on it when the tranny started acting up, dealer did a tranny flush and it ran great for about 5,000 miles then tranny went way south. Dealer wanted $2,500.00 for new one installed, I found a used one with 18,000 miles on it and installed it myself. Installing this was a @#$%. Would not attempt it again. Waiting for (holding my breath) to hear back from general motors on this issue. Transmission shop said to never flush a tranny, thats what made mine go out. They said to only change the filter and fluid. Hope this helps someone out there.

raffjauf, what was your transmission doing before you flushed it??? I've
also got a 2001 and also have about 52K miles on it and for the last
few weeks I can feel each gear change with a bit of a thump, not
always but enough to start noticing something as changed. I also
hear whinning at low speed (transmission??) I have had the transmission
fluid and filter changed but nothing as changed. Am I looking at some
serious transmission problems coming up or is this all normal wear and
tear?????

My tranny was doing the same thing at first, it would "thump" into gear and then a little later would slam hard from 1st to 2nd gear. I was told it was the sun gear going out. I understand there is a service bulletin on this from the dealer but my warranty was already up. If your check engine light is not on yet, it will soon. This is a common problem with these G.M trannys. I would start checking prices to have yours rebuilt. My dealer wanted $2500 to replace it. A transmission shop can rebuild it for about $1200. And yes, your looking at serious transmission problems. I know this what you wanted to hear.

The Montana vans do not have a sun gear in the sense that raffhauf mentions. The problem sun reaction shell was in the 4L60E that comes in rear wheel drives.
You may have a pressure control solenoid going out, which would explain the hard shifts and whine. Best to check the computer for any codes relating to the trans.
If you let it go too long, the rest of the trans will be shot.

My Tranny does the same sometimes (1999 with 210K). The tranny has never been changed and I regularily tow a heavy trailer. When the hard shifting starts i have found that if I stop and put the van in park, and then shut off the van, wait about ten seconds and then start it up again, it usually solves the problem. I have been told by a tranny shop that there is a sensor that sometimes goes south and this is what causes the tranny to shift hard. The tranny apparently goes into a "fail safe mode" and all of the internal pressures are maximized. This is what causes the hard shifting (sometimes you can even hear the whine from the pump in the tranny). Shutting off the van resets the sensor. This has worked for me for three years with no repairs to the tranny at all.

No more Pontiac Montana tranny or intake problems now, am the new owner of a 2005 Hyundia Santa Fe. Will see if this is a better move. Thanks for all your help in this forum.

I was reading the posts on here and could not help but post something myself. Changing your trans fluid and filter and doing a full flush will NOT harm the tranmission. Your manual also states general change intervals, for most driving even that is not enough. If you leave fluid in for too long, old fluid losses its lubricating properties and its heat transfer properties. This only really applies to regular convetional tranny fluid, not fully synthetic fluid. Synthetic fluid has different properties, lasts 10 times longer than convential fluid and is generally better. When clutches and band start slipping, you are creating heat and when the worn fluid cannot transfer the heat quickly the way it was designed to, you are raising the operating temperature of the transmission - killing the transmission. The old saying of keeping all the particles within the oil will help is plain false. If you want to keep fluid in longer, have a full flush with fully synthetic fluid, but be prepard to pay twice or three times the price for the fluid. It is generally accepted that for about every 10% decrease in transmission fluid temperature, you can almost double the life of your tranmission.

airmech,
did the mechanic told you what sensor was going bad? im guessing that it might be the MAP sensor. but my van does not give any SES light at all and i have scanned it for codes but would not yield any.

rajjhauf, I realize you no longer own the Montana but I was curious to know why you did not press the dealer to pay for the tranny replacement etc. Their work is supposed to be warranted for 12 mths/12K mi and the tranny shop said it was their fault the tranny failed. In my opinion 50K miles is nothing unless you're doing lots of mountain driving or towing heavy loads.

someone please explain to me how the tranny shop's fluch machine works.

1) where do they attach in and out to get flow through

2) how the hell can they garantee there is no old residual fluid in the machine from the last flush they perfomed?

3) does the fluid backflow through the filter? Or normal flow?

4) how do they deal with different types of fluid?? (chrysler vs dexron)

Personally, I'd never take my vehicle somewhere to do a flush. I just don't trust the bastards enough to do it right, aside from the above questions.

If auto manufacturers want owners to keep the fluid fresh in the transmission, why do they make them so hard to service?? How about an external filter like engines? How about a drain plug?

my $0.02

my van has started this hard shifting. it doesnt do it all the time. It shifts fine when first starting out but after the van gets warm then it starts but it will quit and start up later. Its kinda off and on thing. Maybe i will try a filter/fluid change too.

someone please explain to me how the tranny shop's fluch machine works.

1) where do they attach in and out to get flow through

2) how the hell can they garantee there is no old residual fluid in the machine from the last flush they perfomed?

3) does the fluid backflow through the filter? Or normal flow?

4) how do they deal with different types of fluid?? (chrysler vs dexron)

Personally, I'd never take my vehicle somewhere to do a flush. I just don't trust the bastards enough to do it right, aside from the above questions.

If auto manufacturers want owners to keep the fluid fresh in the transmission, why do they make them so hard to service?? How about an external filter like engines? How about a drain plug?

my $0.02

1) they usually disconnect the two cooler lines one is connected to drain fluid out, the other is connected to take fresh fluid in.

2)The fluid going in will always be the new fluid, no residue in new fluid tank.

3)The fluid flows normally, the way it is intended to, no backflow.

4)They deal with this by either using the appropriate fluid, or by adding the necessary additive package to the fluid for the specific vehicle.

The last point you bring up is a very good set of questions, an external filter would be a great idea, some rebuilders do put a external filter connected in-line with the cooler lines. As for a drain plug...I still cannot believe they don't pure nonsense...I agree they should.

As for rubberman, or anyone having the hard upshift, get it looked at right away, your destroying your transmission. The extra pressure put on the clutches as shown by the hard shifts, will tear it up. If the problem goes away and comes back, especially if you stop shut it off, and start it again, is usually(not always) but usually an indication of a bad PCS (Pressure Control Solonoid). Don't keep driving it like this, or you will be in for a rebuild.

hell i'll trade in the stupid van before i spend that amount of money on it.

Mine sometimes does the rough upshift thing. I find a spot to pull over, cut the engine off for about a minute, all is fine. There is a pressure valve that could cause it, but a friend of mine changed his valve, and it did not cure the problem.