Dexron VI vs. Mercon V -- accidental quart!

[jerrodl]

Hi All,

Putting this to the experts:
My 2020 Suburban (6L80 6-speed) blew a transmission line and dumped out a lot of the transmission oil. It turned out to be a missing clip that holds the line onto the trans cooler. NAPA sold me a new clip and a some trans oil. It was dark when I put it in, so I put in the four quarts they sold me.

In the daylight, it turns out they sold me three quarts of Dexron VI and one quart of Mercon V (the NAPA brand of both). So.....

I know they're close (from what I've read), but I wanted to ask the experts here: Do I worry about this or just carry on with what I have? Thanks in advance!

 

[ripcord]

Personally, I wouldn't sweat it too much. The transmission takes about 12 quarts total so the percentage of Mercon V is pretty small.

 

[jerrodl]

Yeah, I didn't know which converter GM put in it, so it's 10 or 12 qts, I guess. I'm trying not to sweat it!

 

[MolaKule]

@jerrodl Just make sure you didn't overfill it. Check the ATF level when hot.

 

[kschachn]

And keep the power bait out.

 

[ripcord]

And keep the power bait out.

I think I'm missing a reference?

 

[dogememe]

Mercon LV is very close to Dexron VI. Mercon V is really not. That said, it likely won’t matter much.

 

[RF Overlord]

Agree w/@ripcord. One quart out of 12 won't even be noticed.

 

[MolaKule]

Agree w/@ripcord. One quart out of 12 won't even be noticed.

But we don't really know exactly how much he lost or how much might need to be added.

 

[jerrodl]

I'll be putting in the fifth quart here. The level is still below cold...when cold. It doesn't get real hit here in Minnesota in January, but I'll get it up to temp to get the level checked asap.

 

[jerrodl]

And by close, I mean they're the same base product, right? I have no idea, though.

 

[RF Overlord]

But we don't really know exactly how much he lost or how much might need to be added.

Granted, but either way it's still only 1 quart. If he needs to add more to get it to full, that dilutes it even more.

 

[MolaKule]

Hi All,

Putting this to the experts:
My 2020 Suburban (6L80 6-speed) blew a transmission line and dumped out a lot of the transmission oil. It turned out to be a missing clip that holds the line onto the trans cooler. NAPA sold me a new clip and a some trans oil. It was dark when I put it in, so I put in the four quarts they sold me.

In the daylight, it turns out they sold me three quarts of Dexron VI and one quart of Mercon V (the NAPA brand of both). So.....

I know they're close (from what I've read), but I wanted to ask the experts here: Do I worry about this or just carry on with what I have? Thanks in advance!

I would say that down the line, do a drain and refill and use Dexron VI for the D&F.

The important thing right now is to make sure the fluid level is where it should be.

 

[tcp71]

There was some information at one point that using Mercon V caused transfer cases with clutches to make the clutch material delaminate and wrecked them. I know yours is a transmission but not sure of the clutch material or compatibility. Might be internet myth, may have some truth, I don't know, but maybe something to dig into. Based on something like this:

https://www.ford-trucks.com/forums/...-mercon-v-will-destroy-the-transfer-case.html

This only goes to 2007:

 

[ripcord]

There was some information at one point that using Mercon V caused transfer cases with clutches to make the clutch material delaminate and wrecked them. I know yours is a transmission but not sure of the clutch material or compatibility. Might be internet myth, may have some truth, I don't know, but maybe something to dig into. Based on something like this:

https://www.ford-trucks.com/forums/...-mercon-v-will-destroy-the-transfer-case.html

This only goes to 2007:

View attachment 257821

I don't think that's relevant here

 

[RF Overlord]

When plain Mercon was sunsetted, Mercon V was reformulated to be compatible and back-spec'd for all application that previously had been Mercon-only.

 

[Fordiesel69]

1 qt the tranny wont notice. Sleep well!

Now that you lost 5 qts on the road, plan to do another drain and fill again in the future.

 

[jerrodl]

Thanks for the replies -- all interesting and I appreciate them all.

Here's the update:
I've put in 6 qts of Dexron VI so far and it may be a pint low. It's hard to get a good hot reading when it's about 0 degrees F in Minnesota! For some reason, this Chevy product doesn't read the transmission temperature on the display, even though the manual says it's supposed to. It's not even an option in the settings for the display....believe me, I've checked! Not even the Chevy dealer I spoke with had any explanation for that.

I'll probably dump and refill this spring....when it's warmer.

 

[D60]

I don't think that's relevant here

FTM seems to suggest MercV should not be put in ANY TRANSFER CASE EVER but he seemingly can't provide a reason except apparently the bottle specifically says not to.

I'm all for manufacturer declarations but we should also be allowed to inquire about the reasoning behind those declarations -- simply to learn if nothing else. FTM didn't seem to appreciate challenging the sticker on the bottle (shrug). I love his content but I guess I'm one of those trouble makers who asks questions (which also upset people circa 2020)