ATF change in GM 10 Speed
- Thread starter Kestor
- Start date
No.
Yes.
Not as routine service.
Yes.
Not as routine service.
- Joined
- Dec 20, 2022
- Messages
- 303
As long as they are the same specs, Dexron ULV, you won't have to do a full flush. Dexron requires brands to be compatible with each other.
In our Ford Explorer I went from Mercon LV to Castrol Full Synthetic that was licensed by Ford for Mercon LV use. It was just fine. The build quality of the transmission was a different story though
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Less than half of your trannys capacity is in the pan.
Honestly, if it came with ULV, that's what I would use when doing a flush or drain & fill. It might shift harder or have other minor issues with regular Dex 6 types of fluid. However, my Cadillac has the 9 speed and uses Dexron 6 and my brother has a Bronco Sport with the 8 speed (basically it's the same transmission with one gear tuned out) and his takes ULV.
What year, make, model and trim level and odometer reading, please?
How's it shifting now?
How's it shifting now?
BrendanC
$100 site donor 2024
i have done a few of the 10 speed GM trucks. i run Valvoline ULV exclusively. i personally dump in Lubeguard red but that is up to you.
the work to do this job is the hard part. have to drop the exhaust at both manifolds and let it hang. drop the pan, replace the filter then pull an 8mm allen plug out fill, start it and brake stall on and off until 170-180° then burn yourself pulling the plug out and let the extra spill out.
the work to do this job is the hard part. have to drop the exhaust at both manifolds and let it hang. drop the pan, replace the filter then pull an 8mm allen plug out fill, start it and brake stall on and off until 170-180° then burn yourself pulling the plug out and let the extra spill out.
If I bought a vehicle that came with a ULV / LV ATF I would swap it out (with a pan drop to inspect & clean magnets), probably with Valvoline Maxlife ATF as it's the most cost effective / available to me. Amsoil if I had the cash to spare.
I would NOT run any transmission with an ULV fluid just as I would NOT with an engine. Equipment wear and reliability are more important to me than 5% fuel efficiency and extra wear + failure. My Nissan CVT runs great on Maxlife or Amsoil (both are cheaper than the inferior Nissan NS2 fluid) and my engines that spec 5w20 / 5w30 run really well on 5w30 / 5w40 / 0w40.
BrendanC
$100 site donor 2024
highly recommend against this. with how complex new transmissions are and tightly tied to electronics, i would stay with an ULV if the transmission calls for it.
Thanks for all the information.
2020 gmc 6.2L 100k miles with no noticable issues.
According to the service department at the local dealership, the dex ulv is the "same" as Mobil 1 synthetic lv hp. Is this true? He couldn't answer why one is called ulv and the other lv
2020 gmc 6.2L 100k miles with no noticable issues.
According to the service department at the local dealership, the dex ulv is the "same" as Mobil 1 synthetic lv hp. Is this true? He couldn't answer why one is called ulv and the other lv
- Joined
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There is a reason they spec ULV fluid. I would most definitely not do this. This isn’t quite the Dexron VI debate where one may be compatible vs licensed. Only use a ULV fluid. If you want something non Dexron ULV licensed, many make something that they list as compatible that would probably work.
***I did this and then had to undo it.***
I had the 10r80 and mine was giving me trouble. Of course I tried a fluid change and of course as an amsoil fan I tried the D/F to amsoil. I mean, their website says I could!
First, it didn’t fix the problem, but we will leave that there.
The thicker fluid was notable. At first it just felt like firmer shifts. But really what I think was going on was the thicker fluid delayed completion of the shift, and when they finally locked into the next gear it kinda “slapped” into engagement. It was worse. It was not better.
Lesson learned. Redid with Valvoline ULV with a partial dose of lubegaurd red for the win.
Now - the ford version of the 10r80 showed some bushing galling on the CDE drum (observed in videos). So I ended up with, after those 2 D/F, still a little amsoil in the mix. So, subsequent D/F I stayed with 3/4 ULV and 1/4 amsoil, with 1/4 bottle lubeguard red. That kept a *slightly* thicker fluid and presumably additive pack in there, but on,y slightly.
I traded my f150 recently and it broke down while the dealer test drove it (hard, the evidence suggests). The transmission, with that mix, was not what failed on them. BUT, it was primarily ULV with only a little LV fluid in the mix. A pure LV fluid swap won’t be great. Maybe it will work if you can recalibrate it on the GM (fords implementation has adaptives which one can reset with forscan software).
Back to ULV, it simply shifts quicker and with less drama in that trans.
@Kestor
I had the 10r80 and mine was giving me trouble. Of course I tried a fluid change and of course as an amsoil fan I tried the D/F to amsoil. I mean, their website says I could!
First, it didn’t fix the problem, but we will leave that there.
The thicker fluid was notable. At first it just felt like firmer shifts. But really what I think was going on was the thicker fluid delayed completion of the shift, and when they finally locked into the next gear it kinda “slapped” into engagement. It was worse. It was not better.
Lesson learned. Redid with Valvoline ULV with a partial dose of lubegaurd red for the win.
Now - the ford version of the 10r80 showed some bushing galling on the CDE drum (observed in videos). So I ended up with, after those 2 D/F, still a little amsoil in the mix. So, subsequent D/F I stayed with 3/4 ULV and 1/4 amsoil, with 1/4 bottle lubeguard red. That kept a *slightly* thicker fluid and presumably additive pack in there, but on,y slightly.
I traded my f150 recently and it broke down while the dealer test drove it (hard, the evidence suggests). The transmission, with that mix, was not what failed on them. BUT, it was primarily ULV with only a little LV fluid in the mix. A pure LV fluid swap won’t be great. Maybe it will work if you can recalibrate it on the GM (fords implementation has adaptives which one can reset with forscan software).
Back to ULV, it simply shifts quicker and with less drama in that trans.
@Kestor
4WD
$50 site donor 2025
ULV is only around 4.4 - whereas the blue label Mobil is 5.7 and that’s close to MaxLife … so pretty big difference in viscosity at play with ULV …
GM ULV trans fluid at rock auto is dirt cheap. It's hard to pass up a fluid that meets spec at the price they are selling it at.
4WD
$50 site donor 2025
It’s likely the P66 it came with - so ideal for a partial change
I believe the answer is fuel economy and the related sales boost. I would love to know more.
No such thing as Dexron 6. It's VI, as in V.I.
Same that Dexron LV isn't Dexron 55.
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IMO, with transmissions, I don’t think the whole thick vs thin fuel economy debate really comes into play. They are incredibly more complex and everything has to work just right. The solenoids, valve bodies, and everything else has to be absolutely perfect. We are fitting 10 speeds in a smaller form factor than 6 speeds years ago. Thinner fluids might just have to be present in order to properly lubricate, flow through smaller channels with the overall smaller and more compact size, and everything else.
All my opinion, however.
