Wrong Trans Fluid or not?

[RStocker1]

Maybe someone on this board can clear this up for me. I have a 98 XLS that was due for a trans fluid change a few weeks back. After reading several posts, I decided to do the drain and refill 3 times without dropping the pan. I used Valvoline DEX/MERC, which the Advance Auto people said was compatible. I began noticing the shifting was a little sluggish, so I talked to a Toyota dealership who said they no longer sold the DEX III fluid, since the newer Toyotas used the other type, but that I should NOT use DEX/MERC, but should use just DEX III. So who is correct here?

[toyomoho]

The Valvoline website states this fluid can replace Dexron III. Each type of trans fluid is a little different and the trans may function differently because of this. Different fluids have varying levels of additives, viscosity vs. temp, etc.

My concern would be even if the fluid were OK to use in this trans; you are finding the trans is not operating as it normally does. The likely cause of this is using the Valvoline fluid in place of Dexron III.

I suggest you change back to Dexron III and see if this solves the trans shifting issues. Keep in mind the pan only holds about 1/3 of the fluid, the rest is in the torque converter.

If you are concerned about fluid life, changing the fluid every 30K miles will prevent the fluid from degrading to the point of doing any potential damage to the trans. Trans fluid life is based to a large degree on how hot it gets during operation.

FYI, Dexron III has been superceded by Dexron VI, but Type III is still available at stores.

[RStocker1]

Originally Posted by toyomoho

...FYI, Dexron III has been superceded by Dexron VI, but Type III is still available at stores.

Thanks for the input. So far, I have been unable to find any Dexron III only. Plenty of choices for Dexron III/Mercon, but no Dexron III only, but I'm going to keep looking.

[aznstylez]

I've been wondering what steps did you take to flush out the transmission fluid? So what your steps?

[csaxon]

All DEXRON®-III licenses expired Jan 1 2007 and will not be renewed. That's why it's getting harder to find Dex III. Fluids sold in the market after that date bearing claims such as “suitable for use in DEXRON®-III applications” or similar wording should be avoided. DEXRON®-VI licensed fluids are fully backward compatible and can be used in all applications covered by earlier DexIII specifications. Dex VI is the replacement.

[Mike Murrell]

I switched an automatic transmission that originally called for Dexron-III over to this product. It may be the same one mentioned in the opening post of this thread:

http://www.valvoline.com/pages/produ....asp?product=6

No problems whatsoever.

Is is pssible your transmission is either under or over-filled?

It takes a good 20 miles of consistent driving to warm up a transmission enough to perfrom a fluid level check.

[toyomoho]

A lot of fluids meeting Dexron III specs also meet Mercon specs hence the reason both names are on the container.

I suggest returning to the fluid you had been previously using.