Servicing a 2001 GM 4L60-E, DEX III or VI?

[KeithKman]

I'm doing a pan drop, filter change, and replacing the 5 quarts I remove. I bought Valvoline DEX/MERC which is DEX III. Owners manual calls for DEX III but my understanding is DEX VI is the only GM certified spec now.

Should I take back the fluid I bought and get the DEX VI or can I run the DEX/MERC safely? I don't care about voiding warranty as the truck has over 100k miles. I've seen in other threads on here that when switching to VI the shifts have been a lot softer and some don't like the feeling.

 

[daman]

DEX 6!!!

 

[JHZR2]

Yes, Dex VI. No reason not to in a GM AT.

 

[Oil Changer]

Originally Posted By: JHZR2
Yes, Dex VI. No reason not to in a GM AT.


A BIG +1 to this! Stick with the Dexron VI and don't use Valvoline.

At least check with the dealer on cost. A few extra dollars now may save you lots more later.

 

[3311]

I just serviced a 96 2.2l s10 4l60e with ST Dex VI and it is really shifting nice. Especially with such a embarrassingly underpowered vehicle.

 

[daman]

Originally Posted By: Oil Changer
Originally Posted By: JHZR2
Yes, Dex VI. No reason not to in a GM AT.


A BIG +1 to this! Stick with the Dexron VI and don't use Valvoline.


Why?

 

[The_Jeff]

If you're overdue dump the Dex 3 in you have now then do another change in 5-10K miles with Dex 6.

 

[Oil Changer]

Because Valvoline makes junk and his transmission will most likely fail soon after.

Originally Posted By: daman
Originally Posted By: Oil Changer
Originally Posted By: JHZR2
Yes, Dex VI. No reason not to in a GM AT.


A BIG +1 to this! Stick with the Dexron VI and don't use Valvoline.


Why?

 

[scurvy]

Originally Posted By: daman
Originally Posted By: Oil Changer
Originally Posted By: JHZR2
Yes, Dex VI. No reason not to in a GM AT.


A BIG +1 to this! Stick with the Dexron VI and don't use Valvoline.


Why?

Oil Changer recently had a 4L60E go TU after 4 drain & fills with Valvoline Maxlife ATF, so he is not recommending their products for this application (or anything else, most likely).

I understand that he feels stung by what he considers to be an inferior product that has personally cost him quite a bit of money, but keep in mind the 4L60E is widely known to have sun shell failures among other issues regardless of what fluid was used.

The millions of miles others have put on Valvoline Maxlife ATF (including in the 4L60E) should help you take his advice with a grain of salt; however licensed Dexron 6 is cheap & easy enough to get, there's no real reason to not use it. And yes, even Valvoline makes a licensed Dexron 6 ATF.

Once again, I'm extremely glad all my vehicles have manual transmissions.

 

[KeithKman]

Originally Posted By: eljefino
If you're overdue dump the Dex 3 in you have now then do another change in 5-10K miles with Dex 6.


There are zero issues mixing DEX III and VI correct? Pan drop only changes roughly 5 quarts. My transmission holds a little over 14 quarts so there will be a lot of old DEX III still in the system.

 

[daman]

Originally Posted By: Oil Changer
Because Valvoline makes junk and his transmission will most likely fail soon after.

Originally Posted By: daman
Originally Posted By: Oil Changer
Originally Posted By: JHZR2
Yes, Dex VI. No reason not to in a GM AT.


A BIG +1 to this! Stick with the Dexron VI and don't use Valvoline.


Why?

The reason i asked is because i used Valvoline in the kids sunfire 20,000 miles ago and not one problem,i also used it in my '99 Z71 with 234k and not one problem.

yes i remember your thread,there is nothing wrong with Valvo Dex 6.

 

[daman]

Originally Posted By: KeithKman
Originally Posted By: eljefino
If you're overdue dump the Dex 3 in you have now then do another change in 5-10K miles with Dex 6.


There are zero issues mixing DEX III and VI correct? Pan drop only changes roughly 5 quarts. My transmission holds a little over 14 quarts so there will be a lot of old DEX III still in the system.

I would do a line flush and get it all changed out,you wont get the full benefits of the dex6 if not.

 

[KeithKman]

Originally Posted By: daman
Originally Posted By: KeithKman
Originally Posted By: eljefino
If you're overdue dump the Dex 3 in you have now then do another change in 5-10K miles with Dex 6.


There are zero issues mixing DEX III and VI correct? Pan drop only changes roughly 5 quarts. My transmission holds a little over 14 quarts so there will be a lot of old DEX III still in the system.

I would do a line flush and get it all changed out,you wont get the full benefits of the dex6 if not.


I was planning on changing the fluid in 300 mile incriments since the trans has 152k miles. I was going to drain and fill the pan 3 times total.

 

[RF Overlord]

Either fluid will serve you well in that application. You can certainly use what you have now and use Dex VI for the remaining pan-drops, or return it and go all Dex VI if you'll sleep better at night.

 

[daman]

Originally Posted By: KeithKman
Originally Posted By: daman
Originally Posted By: KeithKman
Originally Posted By: eljefino
If you're overdue dump the Dex 3 in you have now then do another change in 5-10K miles with Dex 6.


There are zero issues mixing DEX III and VI correct? Pan drop only changes roughly 5 quarts. My transmission holds a little over 14 quarts so there will be a lot of old DEX III still in the system.

I would do a line flush and get it all changed out,you wont get the full benefits of the dex6 if not.


I was planning on changing the fluid in 300 mile incriments since the trans has 152k miles. I was going to drain and fill the pan 3 times total.

Thats still not as good because your mixing new with old and IMO you really don't get a full new fluid total exchange.

but its better then doing nothing.

 

[Grebbler]

After hearing from many trans shop secretaries (the ones that field the calls from angry customers) and personally experiencing trans failure after a full flush on an old trans with original fluid I would not do a line flush or pan drop every 300 miles.

Since my trans went (and is still going) on Dex III for 200k miles, that's what I put back in after filter change. I was worried that Dex VI was spec'd for EPA reasons only when it first came out; or that it was too thin or had too much detergent and would plug filter/valve body when whatever deposits in there dissolved. Heck, varnish may be all that's allowing some of the worn seals in my transmission to function.

If your trans is running fine now then pan drops at 10K may be safer.

I know I'm a wuss in the transmission department. It's one component I don't feel I can tackle myself so I don't want to fix something that ain't broke, yet.. I sure don't trust transmission shops around here, anymore.

Whichever way you go, please keep us posted so the myth can be busted or boosted.

 

[friendly_jacek]

+1

Either service correctly from the beginning or don't service at all. If you do service, do things slowly and don't shock the transmission as it will fail if week.

 

[KeithKman]

Took back the Valvoline DEX III and got the Valvoline DEX VI. I guess I'll go longer between the 5 quart changes.

Trans shifts fine now. Hopefully I don't nuke my trans after the pan drop, filter change, and adding DEX VI.

 

[scurvy]

Originally Posted By: friendly_jacek
Either service correctly from the beginning or don't service at all. If you do service, do things slowly and don't shock the transmission as it will fail if week.


I really wish this old wives' tale would stop getting propagated.

If the transmission fails after a change with the proper fluid, it was going to fail anyway. You are always better off changing the fluid than you are not changing it.

 

[cchase]

Originally Posted By: Grebbler
I was worried that Dex VI was spec'd for EPA reasons only when it first came out; or that it was too thin or had too much detergent and would plug filter/valve body when whatever deposits in there dissolved. Heck, varnish may be all that's allowing some of the worn seals in my transmission to function.


Dex VI starts at a lower viscosity than Dex III but also shears substantially less. Typically Dex VI's viscosity through service is actually higher than Dex III.