When did you change the transmission fluid in your 10L80?

[jlong1984]

I'm about to hit 45,000 miles and wonder if replacing the transmission fluid at the "severe service" interval would be beneficial, or should I just let it go another 20-30,000 before replacing it? 

 

GM doesn't give a "normal" transmission fluid change interval, however, they list the transfer case as having a 97,500 mile interval under "normal" use, and it's also 45,000 under the "severe" schedule. 

 

This is the first truck I've kept long enough to even ponder this in a while. 

[diyer2]

I follow severe service. Has worked well.

[Black02Silverado]

I changed mine out at 25k.  I would have done it sooner, more like at 12k but I was hoping to do it myself but nothing was on YouTube at the time and so I just had the dealer do the full exchange.  Cost me $130 and I provided the AMSOIL ATL fluid for them to put in.  So at 75K miles I will drop the pan and change the filter and top up the fluid.  If you are interested in using AMSOIL, let me know and I can send a quote.  They used 14qts to do mine.

 

Edited September 16, 2023 by Black02Silverado

[repairman54]

Follow the severe schedule for things to go the distance. I've taken multiple GM transmissions over 200k miles, FWD and RWD, 4x4, etc. with tow duty, fluid changes are way cheaper than transmission changes. 

No need for boutique fluids either, I've been using Amalie full synth in my fleet for a while now. 

Edited September 18, 2023 by repairman54

[Grumpy Bear]

1 hour ago, repairman54 said:

Follow the severe schedule for things to go the distance. I've taken multiple GM transmissions over 200k miles, FWD and RWD, 4x4, etc. with tow duty, fluid changes are way cheaper than transmission changes. 

No need for boutique fluids either, I've been using Amalie full synth in my fleet for a while now. 

 

Reflecting on my experience it's been a mixed bag of nuts. I confess, I was the biggest nut in the bag early on. My training from infancy (dad) always had me checking level but changing on condition was something that happened when it looked awful. To late! I also never paid much attention to heat. To late! Failures were blamed on abuse, and I did abuse a few, or flaws and both GM and Ford had a few of those as well. Early TH700R and Ford FMX come to mind. 

 

After buying and repairing a few transmissions and paying towing/motel bills I slowed down and started to pay attention to everything. I never had enough money to burn in a pit. 

 

Started changing ATF on the severe schedule and leaving the abuse to the track car. What an impact that had on service life! Instead of three or four transmissions per 100K, like you, it was one per 200K. Until Full Synthetic became a "thing" same service was expected on good oil mineral oil and I was getting it. 

 

Then the EPA got involved and the OEM's got greedy(er). It wasn't enough to have fluids designed to sub 7 cSt specs, they added TBV's to them to push them to heats that had us running for coolers in our earlier days except they didn't really work with the TBV's.  Mineral oil wouldn't tow the mark and synthetics were not just the next best option but the benchmark to handle these heats and yet they cannot. They ran that hope over as well, setting limp mode triggers in the OMG range and living with fatal flaws of design betting against the odds of warranty dollars and human endurance for BS. Universal builds across multiple manufactures assured that a brand change did nothing to help. The response to all this was spinning a tail that "Synthetic Fluids will handle any heat we say they will" and a public willing to drink that swill. 

 

While many as individuals were having some success, as a group the failure rate became high enough to issue new parts such as the 70C TBV and ELIMINATING them on the HD trucks. Removing the TCM form that hot oil bath. Redesigning the cooler layout ever few years and morphing into something that, for the most part, works.

 

Starting with the 8L, redesigning the fluid from the ground up for moisture and friction package issues. 

 

Something the boutique oils considered before GM/Ford even knew they had an issue. 

 

Guys like you are PROOF it can be done without them, but guys like you are also not "Joe Average". Joe Average in our day could rebuild the entire car. Joe today can't tell the difference between a sparkplug and a fireplug. 

 

Are they NEEDED? Nope. But I find my life goes so much smoother when I'm using good tools.  

 

 

[jlong1984]

Went ahead and booked the appointment. Going to get the transmission, as well as the transfer case and differentials done. Planning to make this truck last a while. 

[Bikerjon]

Very good decision.

[SC4R3C120W]

i drive a lot, typically over 30k miles a year (bought in May 2020 and already have 101,600 miles on it). I had dealer do the flush at 50k, and a flush with filter at 101k. When i went in for the 101k service, i had to ASK for the filter to be changed. Guess they don't see it's needed unless you have problems, but i like to be proactive and had it done anyway

[Black02Silverado]

On 9/21/2023 at 1:06 PM, SC4R3C120W said:

i drive a lot, typically over 30k miles a year (bought in May 2020 and already have 101,600 miles on it). I had dealer do the flush at 50k, and a flush with filter at 101k. When i went in for the 101k service, i had to ASK for the filter to be changed. Guess they don't see it's needed unless you have problems, but i like to be proactive and had it done anyway

It is crazy that they don't want to do the filter change but just do a flush.  Good that you had them do that.  I'm sure it needed it.

[davidr83]

Im almost at 38k miles and mine is going in tomorrow for fluid exchange and filter change. Im hard on mine and after my cam swap, the tuner recommended this be done at 40k miles from what they've seen. They dont do the fluid exchange at their shop so I didnt see it as a sales pitch and more of a heads up to get it done so i will.

[diyer2]

I have used Jiffy Lube for a fluid change and filter replacement. Don't know if they still do it. Last time was a while ago on my 93 1500,so a 4 speed. I think it was $125. Worth a call. I would guess 8-10 years ago.

[relevante]

I was a little on the fence about keeping the truck or trading but just decided to commit to keeping it so I did the trans fluid and filter at 67k. I do some occasional towing and drive pretty hard on the highway on road trips, but this truck generally lives a pretty easy life. I’m pretty sure the hottest the trans has ever been was yesterday when I had to bring it up to the specified temp to set the fluid level.

 

The old fluid didn’t look bad, appropriately dark and smelled fine, but it and the filter were dark enough that it felt like time well spent, but good enough that I didn’t feel like I blew it by not getting around to it until now. It’s not really a bad DIY. Just have to remove the three bolts on each side (much easier with the fender well liners out) to remove the Y pipe from the exhaust manifolds and lower it. I disconnected the O2 sensors but that probably wasn’t even necessary since I didn’t remove the pipe entirely or remove the crossmember mentioned in the service manual and the pan came out without much trouble. I also pulled one of the drivers side O2 sensors out just to get easier access to one of the manifold nuts, but no big deal. I did buy new exhaust seals as recommended, and I’m glad I did as the passenger side ring was worn down quite a bit. I bought 10 quarts of fluid (GM Dexron ULV) and ended up using 9.5.

Edited November 16, 2023 by relevante

[diyer2]

If you want it to last keep all the fluids changed using the severe duty schedule. Has worked for me for many years. Every truck I have owned went over 250k miles.

[Mshawn]

On 9/15/2023 at 8:32 PM, Black02Silverado said:

I changed mine out at 25k.  I would have done it sooner, more like at 12k but I was hoping to do it myself but nothing was on YouTube at the time and so I just had the dealer do the full exchange.  Cost me $130 and I provided the AMSOIL ATL fluid for them to put in.  So at 75K miles I will drop the pan and change the filter and top up the fluid.  If you are interested in using AMSOIL, let me know and I can send a quote.  They used 14qts to do mine.

 

Noticed any difference in the way it shifts? Guys over at the ford forum( 10r80) says it messes with the shifting because of the viscosity rating. I like amsoil product and I’m going to change everything I’ve to amsoil in my 2023 RST

[Black02Silverado]

34 minutes ago, Mshawn said:

Noticed any difference in the way it shifts? Guys over at the ford forum( 10r80) says it messes with the shifting because of the viscosity rating. I like amsoil product and I’m going to change everything I’ve to amsoil in my 2023 RST

If shifts great. No issues. It’s my understanding the Ford 10sp tune is way different and that’s mostly the issues they are having. I have 25k on the fluid so far.