Ford 10R80 transmission woes

[BlueC]

So again, the issue is only apparent on long, sustained, high speed highway travel at higher speeds.

What on earth could that be about?

Just a guess here, but maybe the extra load is causing slippage, thus building heat. Try pulling a trailer with some weight at lower speeds and see if you have the same issue. If so, based on what I've read here, I'd say the transmission doesn't like the new fluid and/or filter. Some vehicles are very picky, especially with fluids.

 

[Chris]

Just a guess here, but maybe the extra load is causing slippage, thus building heat. Try pulling a trailer with some weight at lower speeds and see if you have the same issue. If so, based on what I've read here, I'd say the transmission doesn't like the new fluid and/or filter. Some vehicles are very picky, especially with fluids.

Yeah, I'm thinking it's related to the sustained high speeds and the torque convertor lockup.

None of these issues were present until I had the transmission fluid changed. The correct fluid was used (I verified).

This is just proving my point about everything becoming crappier in ever aspect of life.

No transmission should (or needs to) be this complicated.

 

[Zorba]

I jinxed myself thinking this transmission fiasco was fixed.

Haven't had any issues for a while now. We took a trip this weekend to Rapid City, South Dakota with the kids to hit up some of the big stores (Scheels) they don't have here in Gillette.

The trip is roughly 2 hours and I averaged about 85 MPH the entire way. When driving there I had the transmission overheat twice when I was about 20 minutes outside Rapid City. I had to pull over, let it cool down, and then it was fine again.

It appears that this problem is only happening when driving for long periods of time at sustained highway speed.

I used my FORScan Lite iOS app and did some data logging today. The transmission didn't overheat once on my 20 minute drive into town today or on the way back. In fact, the transmission temps were more than fine. From our house on highway 50 into town I average 75 MPH for a sustained 15 minutes as well.

So again, the issue is only apparent on long, sustained, high speed highway travel at higher speeds.

What on earth could that be about?

I lived in the Rapid City area - as a babe in arms, so I don't remember anything. A certain GMC pickup was purchased new at the dealership in Pierre...

Maybe your tranny wants you to go the speed limit?

 

[BlueC]

No transmission should (or needs to) be this complicated.

I completely agree with that, and I know you mean that more broadly too.

None of these issues were present until I had the transmission fluid changed. The correct fluid was used (I verified).

I have three questions there, 1 - how did you verify it?, 2 - does "correct" fluid mean FoMoCo branded, or any label "in-spec"?, 3 - same for the filter?

 

[Chris]

I have three questions there, 1 - how did you verify it?, 2 - does "correct" fluid mean FoMoCo branded, or any label "in-spec"?, 3 - same for the filter?

Checked the invoice for the work and called the shop as well just to make sure.

Mercon ULV is what was used. He told me it was FoMoCo fluid, same for the filter. He said they use OEM parts in most cases.