waflyboy Posted December 12, 2023 Report Share Posted December 12, 2023 About a year ago I read @colinc755's suggestions about servicing the 8F35 transmission fluid. At that time, with 65,000 miles on the vehicle, I had our local Ford service department drain and fill the transmission. (I do not believe it had been done prior to this.) This seemed to resolve some of the hard shifting and bucking which manifested from the transmission at the time. Yesterday, a year later, with 85,000 miles on the vehicle, I had the same service done (along with changing the PTU and rear differential oil). I requested that the tech collect a sample of the old fluid for me, as I'd like to have an analysis done. I found the sample to be nearly black in color. Correct me if I'm wrong - but isn't the ULV fluid red when fresh? For what it's worth, I didn't notice any distinct "burnt" smell. The transmission seems to work okay, with no more hard shifting and bucking than the last 60,000 miles we've had the car. But based on the fluid color I wonder if I have an impending transmission failure. Wondering if the hive mind has any thoughts on this. I'm expecting the lab results from Blackstone in a couple of weeks. Hopefully that will provide some insight. Quote Link to comment Share on other sites More sharing options...
dabangsta Posted December 12, 2023 Report Share Posted December 12, 2023 I think Mercon ULV is like Mercon LV, and it starts out darker red and get really dark really quick. When the first Mercon LV vehicles came out Ford published a document that fluid color, as long as not brown or smelling burnt, is not a good indicator of health of fluid or transmission. Obviously a lot of solids in it is bad also. Quote Link to comment Share on other sites More sharing options...
waflyboy Posted December 12, 2023 Author Report Share Posted December 12, 2023 @dabangsta Good to know, thanks for the info. In that case, hopefully the analysis doesn't show anything unusual. Quote Link to comment Share on other sites More sharing options...
lildisco Posted December 13, 2023 Report Share Posted December 13, 2023 (edited) Here's the 1st drain & fill I did on our 2020 SEL a few weeks ago just under 27,000. Edited December 13, 2023 by lildisco Quote Link to comment Share on other sites More sharing options...
lildisco Posted December 13, 2023 Report Share Posted December 13, 2023 (edited) This is from the 2nd drain & fill, slightly more red, but not a lot. It is my understanding that the OEM ULV fluid turns dark pretty quick. Someone suggested Valvoline makes a ULV fluid that stays red much longer than the OEM. Edited December 13, 2023 by lildisco Quote Link to comment Share on other sites More sharing options...
lildisco Posted December 13, 2023 Report Share Posted December 13, 2023 I also swapped the PTU Fluid to Redline Lightweight Shockproof (AKA Smurf Blood, because it's blue). After ~8,000 miles, there's way less gunk in it, compared to OEM, but with ~8,000 miles, that's nothing on new fluid, but I wanted to make sure that I got as much of the OEM fluid out of there. The 1st pic is the 1st drain with the OEM fluid & this is the most recent drain with Redline Lightweight Shockproof Quote Link to comment Share on other sites More sharing options...
waflyboy Posted December 13, 2023 Author Report Share Posted December 13, 2023 @lildisco Thanks for sharing! Perhaps then it's fairly normal for the fluid to go dark. So is it the fluid or the transmission that causes this? On every other car I've owned, the fluid remained quite red and clean pretty much until the transmission started to fail. Quote Link to comment Share on other sites More sharing options...
lildisco Posted December 13, 2023 Report Share Posted December 13, 2023 To my knowledge, there's no filter in these transmissions, so any wear from the transmission just sits in the coolant & cycled through everything. When I do another 3x drain & fill I'll probably switch to Valvoline. Probably by that time MacT will have changed his 2019 fluid a couple of times & report on the results. Quote Link to comment Share on other sites More sharing options...
dabangsta Posted December 13, 2023 Report Share Posted December 13, 2023 It does have a filter, and while it isn't user serviceable it is more like ones that are, not just a screen in between the case halves, but at bottom of the pump. 1 Quote Link to comment Share on other sites More sharing options...
lildisco Posted December 13, 2023 Report Share Posted December 13, 2023 1 hour ago, dabangsta said: It does have a filter, and while it isn't user serviceable it is more like ones that are, not just a screen in between the case halves, but at bottom of the pump. Thanks. I guess it is serviceable when you split the trans open, lol. Here's MacT talking about the ULV fluids: https://youtu.be/kJQW6wXS0qg?si=e4Hbwa7tYkCXaygT Quote Link to comment Share on other sites More sharing options...
waflyboy Posted January 16 Author Report Share Posted January 16 Here is the fluid analysis from my original post. Aluminum and copper are 9x the "universal average". Iron is 2x. It would be interesting to compare numbers from other 8F35s. The transmission seems to shift ok. Guess I'll take Blackstone's advice and check it again in 10k miles. Anybody have thoughts or experience with this? Thank you. Quote Link to comment Share on other sites More sharing options...
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