4t65e which ATF?

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Hi All.
First time posting, but ive been reading the posts here for quite a while.
I have the dreaded 4t65e (Chevy Venture)that shifts hard when the transmission heats up.
I am adding a shift kit and changing the filter.
Which fluid should i use? I dont want to spend too much as this vehicle isn't worth much at all.
Also I live in Hawaii so i am limited to what i can get locally as it is a pain to get fluids shipped here.
some options i have found are:
Maxlife atf
Napa DexIII (cheapest)
Supertech Dex VI
Castrol HM

Thanks!
 
Maxlife dex merc is one of the best choices.

Once you get hard shifts in the 4t65e the shift kit is too late, assuming it's max adapt hard shifts from worn clutches. The good news is you can drive it shifting hard for awhile, I got a couple years from mine before I finally had a proper rebuild done.
 
I don't believe that DEXRON VI is a recommend ATF for your tranny although, I don't know that you can't use it. It is a low viscosity ATF and so is the MaxLife. So, I would want for myself possibly the Castrol HM or just regular DexIII.

Others will chime in with better recommendations.
 
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I use Valvoline Maxlife Synthetic ATF in my 2010 4t65e, it shifts better with that than Dexron VI.

Also Google "4t65e magnet upgrade" to see if your model would benefit from adding a second magnet to the pan. There was a TSB for my model that added a second magnet to the filter housing to trap more particles. The shift solenoids are magnetic and get clogged up with metal particles with higher mileage. Frequent fluid exchanges and a second magnet have greatly improved my shifts.

Between a TransGo shift kit, a new filter, the second magnet and a few drain/fills with Maxlife, it's like a new transmission. FYI, I have 116K on my 4t65e. It started acting up around 100K when I did all the work, has been good since. It had been serviced @ 60K with new Dexron VI fluid and a filter so it's not like it was neglected either.
 
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My 2001 Grand Prix (3800V6, 4T65E trans) started shifting hard when hot (any city driving at all) sometime around 100-110k miles on it I'd guess. I put a shift kit in it at 120k and when I gave it away just shy of 230k miles it was still shifting fine with the occasional firm shift (nothign like the banging it had before the shift kit however). I did pan drop and filter changes every 30k miles. I used mostly Dex VI and nothing else worked better. I used Mobil 1 ATF the first 90k miles and later it its life I tried Redline D4 but it was no different. I'd probably go with the Maxlife if I were you.

Here is a UOA of mine.

https://bobistheoilguy.com/forums/ubbthreads.php/topics/2705927/2001_Grand_Prix_(4T65E)_Valv._
 
Lot's of talk about this topic on this site and other forums as well.

My personal opinion is to skip the shift kit and the Dexron VI, I would only recommend Dexron VI if the transmission was operating normal. This is a well documented issue with these transmissions that happens as the clutches wear down so I would use a dedicated high mileage atf (castrol transmax) since a higher viscosity is needed. If the pan has hard metal bits in the gray sludge, add the upgraded magnets. GM put out a TSB back in 2009 or so and basically all GM hydramatic electronically controlled transmissions are to receive the updated magnet whenever the pan is dropped. Do a google search for the TSB and the instructions about adding the magnets as each transmission model has a different procedure.

The 4Txxe transmissions are so reliant on those solenoids that any metal particulate that gets attracted to a solenoid will cause problems guaranteed. The stronger magnets help correct the line pressure problem and help prevent the problem from getting worse. Frequent fluid changes along with the upgraded magnets can also help fix the problem in the long run if indeed the solenoids have contaminants on them. Your issue sounds more like a worn out clutches but the magnet upgrade wouldn't hurt. Keep us informed on your progress!
 
welcome2.gif


Any of them will be fine. Maxlife is very popular on here.
 
We had a hot slam banging 4t65e and when I called the tranny shop he instantly replied... "Those are my bread n butter". No kidding. I hated that transmission.

He said they put in a shift kit and add a cooler and they go for 30-60k more, if they had been slamming already. If done preemptively.... then he said it would go several hundred k miles.
 
First off, even if a car’s not “worth much” the cost of a replacement car can be a lot!
If you can "TLC" an older car and get 2 more years, that's a plus!!

So the book value of a car is not something I think about, rather the cost to get another
car that can be avoided! Lol

Clutch pack wear is like No 99 reason for hard shifts. There so many more common problems
for hard shifts that will cause damage that are all centered around a cheapen-out
valve body parts.

Shift kits in the #1 / #2 shift accumulators work great, easily done with the oil pan off.

New oil filter a good bet too.

1 or 2 cans of Seafoam Trans Tune before you pour in new ATF.

Disconnect the car battery for 30 minutes to reset the computer, you likely have a P1811 code
in the TCM. A P1811 forces the line oil pressure so high it’ll damage other things like jamming
the torque converter lockup clutch to ‘on’ and stay there, you’ll have to tear everything out
and replace the torque converter!

Finally be very sure the tranny fluid level is right. If it’s at the lower limit it can start
shifting badly even after all this work. Drive for 5-6 miles, then check level while hot, idling
and in park on level ground. Mine has to be at the top mark on the dip stick. Checking dipstick
level after only idling the engine til the engine is ‘hot’ is not the same as a ‘hot’ tranny!

Good items to read:

HOW GM DEALERS AVOID TRANSMISSION REPAIRS
https://app.box.com/s/rjmdo7p32jtv630a5i7qzaozzr9o98oq


GM 4T65-E COMMON TRANSMISSION PROBLEMS
https://app.box.com/s/n3eaao2pzopusd3bx8qrd7xmgaibj3n1


GM 4T65-E TRANSMISSION UPGRADE PARTS
https://app.box.com/s/drsf61akkxu6bw2a2qcnl1ajuhgkh9hx


ALERT: AFTERMARKET TRANSMISSION FILTERS
https://app.box.com/s/sqsa3zk7pshzojavmkg9


AUTOMATIC TRANSMISSION SERVICE - WHAT YOU NEED TO KNOW
https://app.box.com/s/kwafw6szynq6ma9nk00b
 
Oops! Forgot to mention.

If don't actually do towing, a tranny oil cooler on a 4T65e will set a OBDII code saying the
tranny is too cold and adaptive shifts and even torque converter lockup will be disabled!

Yup! We can't catch a break with GM LOL!
 
Thanks for the replies!
I will definitely order those magnets.
I already have the shift kit so that will go in as well.
I'm thinking of using the cheap dexIII and running it a few thousand miles to see what the magnets pick up. After that switch to a HM ATF.
This van was inherited and is an extra vehicle that gets driven once or twice a week. With a blue book of less than $1500 its not worth selling , but if a cheap fix will let it run a few more years that would be great.
 
Will go for Valvoline Maxlife if I needed to choose from that list.
 
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No need to use a mineral dex/merc when you can get DexronVI for about $4.25 a quart at Walmart which is technically a synthetic.

Maxlife is a superior fluid and if you buy it in gallon jugs it's the better option. I can get a gallon at Meijer for $17.

DexronIII is not currently available, the license is expired so DexronVI is indeed the correct fluid. Lots of people recommend DexronIII but what they really refer to is usually mineral based Dex/Merc and they can be fine fluids for shorter intervals but try to stick to quality brands since they don't have much they are required to pass they vary wildly in quality which is why DexronVI is a better choice since all DexronVI fluids that are legitimately licensed are required to use the GM additive package and a very specific base oil requirement as well.
 
I live in Hawaii so I am limited to Walmart, Oreilly's, Napa, Carquest, and independents.
Only place i can find Maxlife in stock is Oreilly's at $30 a gallon.
DexVI averages $9-$11 a quart
My Walmart rarely has dexVI(about $5 qt.) in stock. In Hawaii Walmart does NOT price match online prices, does not have free shipping, does not have ship to store or pick up in store.
The joys of living in the middle of the ocean. lol
 
I would NOT use a Low Viscosity formulation in that transmission, especially when it's already hard shifting. Unless you want to put it out of it's misery quicker...
All the synthetic formulations are LV, exception being Mobil 1 and Amsoil (they have both variants). They create less operating pressure than the conventional fluids, and with the worn transmission pump, pressure it will be even lower.
That's why the shifts hard when the transmission heats up - the fluid becomes thinner. Probably the additives are depleted, so it's viscosity drops very low.

For that transmission the best you can get now is Castrol HM. The drain and refill needed to be done at every 30-40K miles. If the fluid comes out grey, do again a drain and refill after some 200 miles.
 
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Originally Posted By: CocoNut808
Thanks for the replies!
I will definitely order those magnets.
I already have the shift kit so that will go in as well.
I'm thinking of using the cheap dexIII and running it a few thousand miles to see what the magnets pick up. After that switch to a HM ATF.
This van was inherited and is an extra vehicle that gets driven once or twice a week. With a blue book of less than $1500 its not worth selling , but if a cheap fix will let it run a few more years that would be great.



There was a GM service note on this, google "4T65E magnet update" As usual, GM's fix was rather lame,
you really need 5 or more magnets. But be careful, the oil pan is "zero clearance" with only a few spots
that have space for any magnets at all. Test fit the oil pan to see where it won't seat to the tranny casting.
The metal on the filter right near the oil pick up is a good spot for bar magnets. The rest of the filter actually
sits right on the oil pan with just 1/8" clearance!


Be sure to run it at least 5,000 miles before you look at the magnets for pick-up, some trannies are super
sensitive to wear metals in the ATF due to the particular defect in the valve body and valve and circuit affected.
So if you see a little or a lot, I'd go with how the tranny functions on a day to day basis. The mags will pick
up stuff for sure anyhow.


I've had the pan off my 4T65E so many times as I experimented with more and more part changes and added magnets,
I decided to reuse the ATF until I decided what would be my permanent fix.

1) I wipe down all possible dirt on the oil pan and gasket area, subframe, as well as everything else.

2) Use a clean oil catch pan that's big enough to hold 7-8 quarts of ATF
I use a deep lid (18" x 20" 3" deep, etc) off a large rolling plastic storage bin 80 litre size.

3) Pour the ATF thru a metal coffee filter basket sitting in a big clean funnel into 2 clean and dry
1 gal plastic jugs to use over.

4) Been doing this for the past 3 years of working thru a bad 4T65E - no problems.

5) Yes, it seems cheap and risky, but not for me. Just never let water get into any ATF, new or used.
Water kills clutches.

My 4T65E is finally performing the way it should with nearly no hard shifts over many months and
no OBDII codes set.


A pal has it so bad, he's machining a 1/2" thick aluminum gasket spacer to create room in the oil pan
to use 11 3" ring magnets all over the pan to get rid of hard shifts. Either that or spend $2,600 to
rebuild with tons of Sonnex parts!
 
Originally Posted By: SoNic67
I would NOT use a Low Viscosity formulation in that transmission, especially when it's already hard shifting. Unless you want to put it out of it's misery quicker...
All the synthetic formulations are LV, exception being Mobil 1 and Amsoil (they have both variants). They create less operating pressure than the conventional fluids, and with the worn transmission pump, pressure it will be even lower.
That's why the shifts hard when the transmission heats up - the fluid becomes thinner. Probably the additives are depleted, so it's viscosity drops very low.

For that transmission the best you can get now is Castrol HM. The drain and refill needed to be done at every 30-40K miles. If the fluid comes out grey, do again a drain and refill after some 200 miles.


They hard shift because of worn clutches tripping the max adapt mode because shift times are too long. DexronVI won't affect this.

I would use the Supertech DexronVI which is the same as the name brand.
 
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