Need help, my 2004 Lesabre shifts hard.

[BuickGirlFromMars]

I'd switch back to dex3...other stuff is too thick

Dexron VI is not thicker than Dex 3 unless its at high temperature. At high temperature, Dex VI is slightly "thinner" than cold but its night and day difference with Dexron III hot/cold

 

[SAYBER]

Dexron VI is not thicker than Dex 3 unless its at high temperature. At high temperature, Dex VI is slightly "thinner" than cold but its night and day difference with Dexron III hot/cold

Yup. Sorry, I was at work when I typed that...still would switch back.

 

[Snrnd]

Yup. Sorry, I was at work when I typed that...still would switch back.

Can you explain why you'd switch back specifically? Other forums, people are touting the Dex 6 (Valvoline High Mileage ATF), so that's what I was planning ('04 at 183k miles)

 

[SAYBER]

Can you explain why you'd switch back specifically? Other forums, people are touting the Dex 6 (Valvoline High Mileage ATF), so that's what I was planning ('04 at 183k miles)

I'm a firm oem man, a lot of hours of r&d into these cars and the transmissions are already touchy to begin with. I stick with oem. Im a if it ain't broke, don't fix it kinda guy.

______________________________

 

[Snrnd]

I'm a firm oem man, a lot of hours of r&d into these cars and the transmissions are already touchy to begin with. I stick with oem. Im a if it ain't broke, don't fix it kinda guy.

But is is broke, kinda. Worse case scenario, I drain and refill with Dex 3 again I suppose

 

[BuickGirlFromMars]

But is is broke, kinda. Worse case scenario, I drain and refill with Dex 3 again I suppose

if you drain out dex 3 for dex 6, then drain out dex 6 for dex 3, you are not very wise or intelligent with money or understand simple concepts. however, it is your car. if you want to do it for fun then sure you can

 

[Snrnd]

if you drain out dex 3 for dex 6, then drain out dex 6 for dex 3, you are not very wise or intelligent with money or understand simple concepts. however, it is your car. if you want to do it for fun then sure you can

No need to be an ass about it. Never done this, which if you read my OP you'd know.

 

[BuickGirlFromMars]

No need to be an ass about it. Never done this, which if you read my OP you'd know.

Im not gonna lie I dont know how old this thread is but I dont think you were the one to suggest the procedure first.

If Im true about that, youre simply someone trying to ascertain the best thing you can do for your car which you shouldnt feel bad about

I also make no apologies for not remembering what the first post was, lol.

______________________________

 

[Snrnd]

Im not gonna lie I dont know how old this thread is but I dont think you were the one to suggest the procedure first.

If Im true about that, youre simply someone trying to ascertain the best thing you can do for your car which you shouldnt feel bad about

I also make no apologies for not remembering what the first post was, lol.
View attachment 37683 View attachment 37684

This is why I said "my" OP, and not "the" OP. Either way, not sure how the comment was helpful.
The problem is there are so many posts of saying to do this or that, and everyone has their anecdotal "proof" as to what is best. Even trying to look at the science behind the chemicals can support or go against what people suggest. Yes, I am trying to learn and I don't feel bad about it, and have never said anything to suggest that. I'd rather hear why switching back and forth (other than the cost factor) is actually a bad idea since Dex 3 and 6 are supposedly compatible, instead of how I miss the mark on being competent on simple concepts. This I already assume is true, which is why I found this thread in hopes to grow. Apparently others still have questions, too. I'm grateful for all the help people are giving.

 

[SAYBER]

This is why I said "my" OP, and not "the" OP. Either way, not sure how the comment was helpful.
The problem is there are so many posts of saying to do this or that, and everyone has their anecdotal "proof" as to what is best. Even trying to look at the science behind the chemicals can support or go against what people suggest. Yes, I am trying to learn and I don't feel bad about it, and have never said anything to suggest that. I'd rather hear why switching back and forth (other than the cost factor) is actually a bad idea since Dex 3 and 6 are supposedly compatible, instead of how I miss the mark on being competent on simple concepts. This I already assume is true, which is why I found this thread in hopes to grow. Apparently others still have questions, too. I'm grateful for all the help people are giving.

All I'm saying is what I'D do. Anyone else is free to do what they want. I've heard from people switching to a different weight fluid and immediately having issues. It seems logical to me to stick with what works. I've been driving over 40 years and always use what a car comes with or is suggested by the manufacturer. It's always served me well. I change my oil every 3000 and atf every 30-35,000. May be allittle overkill but I sleep better and have NEVER had an issue. To anyone having the shift issues, I'd do the kit, dex3, filter and grommet and have a nice day. and also don't go throwing 20 magnets in the pan and on the filter, it's foolish and to many magnets could interfere with solenoid function.. I used one small neo magnet in the stock pan location and that's it.

 

[John Canon]

 

[2007LucerneCXL]

I used Mobil HyJet aviation trans fluid and the car really feels different, but take offs are a little hard on the tires.

As a side note the addition magnets are a GM TSB and while not admitting that the original single magnet has issues. It's fact based not forum opinion based and it's a do or don't but not knowing about it owners do not even have that option.

______________________________

 

[Snrnd]

I used Mobil HyJet aviation trans fluid and the car really feels different, but take offs are a little hard on the tires.
View attachment 37688
As a side note the addition magnets are a GM TSB and while not admitting that the original single magnet has issues. It's fact based not forum opinion based and it's a do or don't but not knowing about it owners do not even have that option.

I got the magnets off the TSB and will be sure to install when I do everything.

 

[2007LucerneCXL]

Some items are preventive and others are corrections with design problems. Putting things into perspective once a vehicle has passed the manufacturers warranty all parts are suspect lol.

Good luck on getting the problem resolved and happy motoring.

 

[SAYBER]

I used Mobil HyJet aviation trans fluid and the car really feels different, but take offs are a little hard on the tires.
View attachment 37688
As a side note the addition magnets are a GM TSB and while not admitting that the original single magnet has issues. It's fact based not forum opinion based and it's a do or don't but not knowing about it owners do not even have that option.

Yeah, I know about the magnet bulletin from gm.

 

[lbear]

GM engineers came up with the TSB on the 2 magnets in the trans pan to help prevent the shifting problems from developing. The magnets catch the metallic clutch material that the trans filter CANNOT catch and prevents the metallic material from surrounding and attaching to the shift solenoid, which causes the shifting problem.

The metallic clutch material is so tiny that the trans filter does not catch most of it. It passes right through the trans filter and makes its way into the trans, causing problems.

As long as the 2 magents are placed in the correct place the GM engineers called out for in the TSB, there will be zero issues with messing with anything due to the magnetism.

______________________________

 

[SAYBER]

GM engineers came up with the TSB on the 2 magnets in the trans pan to help prevent the shifting problems from developing. The magnets catch the metallic clutch material that the trans filter CANNOT catch and prevents the metallic material from surrounding and attaching to the shift solenoid, which causes the shifting problem.

The metallic clutch material is so tiny that the trans filter does not catch most of it. It passes right through the trans filter and makes its way into the trans, causing problems.

As long as the 2 magents are placed in the correct place the GM engineers called out for in the TSB, there will be zero issues with messing with anything due to the magnetism.

I thought the the springs inside the accumulator weaken over time, that's why you get stiffer springs in the kit. I've not had any issues with my solenoids.

 

[lbear]

I thought the the springs inside the accumulator weaken over time, that's why you get stiffer springs in the kit. I've not had any issues with my solenoids.

The GM TSB reads for the 4T65e:

This bulletin is being revised to add 2010/2011 model years. Please discard Corporate Bulletin Number 08-07-30-040B (Section 07 - Transmission/Transaxle).

A new transmission oil pan magnet, P/N 29535617, was released for service. The current square transmission oil pan magnet may become saturated with normal ferrous sediment and the Pressure Control Solenoid (PCS) is now collecting ferrous sediment, making it vary from design. For a given current the PCS electromagnet is stronger, causing the line pressure to be less than needed.




So the original factory magnet cannot hold the metal particles and the particles get past the trans filter and end up attaching themselves to the PRESSURE CONTROL SOLENOID. the PCS is magnetic so it basically attracts all the metal particles in the trans fluid and the PCS gets covered in the ferrous material. This makes the PCS fail and the line pressure to drop.

 

[2007LucerneCXL]

One of the symptoms is the bang shift from a stop once the transmission warms up and the fluid pressure drops. Depending on make and model year GM transmission service recommendation 50-100k along with operating conditions so at some point the magnet could become over saturated and material is introduced back into the transmission creating problems.

Regular fluid and filter changes prior to the OEM magnet becoming over saturated is one method, but unfortunately most owners will be looking at that option "the day of" and it's usually to late. It's a cheap way to have addtional protection and easy enough when doing the fluid and filter changes.

Thanks lbear for the post with pictures.