I got my 700R4 for my 89 back and they say to use Dexron IV in it. Was going to use AC Delco brand but found there are 2 different part numbers for them. What brand is the best to use and what part number? This is just a street not a hard core race car. Thanks

 

Dexron III is what GM called for, but for the same price at Wal-hell(mart) I get the Valvoline ATF in the burgundy 1 Gallon jug that is compatible with Dexron III-VI. It advertises as being fully synthetic. It has worked great in my 4L60s and 4L80s I have used for towing. From the write-ups I read it has more additives to increase clutch life and can take higher temps. It also adds 15 hp (j/k).

 

Be careful with the Valvoline synthetic Dex IV. If you read the front of the label it may say "High mileage" I tried this in my fresh built 4L80e and it caused a little slipping. So I drained it out and tried Valvoline synthetic Dex IV in the blue jug without the "high mileage" on the label and it ran very well. Also I noticed almost a 10 degree loss in temp between Dex III and Dex IV. But for whatever reason the high mileage stuff gave my new trans issues. I got the blue jug Dex IV at a Advance auto parts. I'm not sure if Walmart has it or not.

 

I use it in my 01 Tahoe that I tow 5000 lbs with and my 01 Suburban 2500 8.1L with a 4L80 that I tow 11,000 lbs with. I rebuilt the 4L60 as my first trans. No slipping in either and that's towing to their max capacity.

 

AC Delco Dexron-VI, my buddy who's been a GM Technician for over 35 years is my transmission guy, he's certified by GM to open and rebuild/fix any transmission in the GM lineup and also builds transmissions when he gets home.....I asked him what to put in my '84 and this was the recommendation! I've put it in ALL of my GM automatics '78, '84, '96, '04, '07, all of them still going strong👍

 

Dexron VI supercedes III and II. Any licensed IV will work fine. The license for III hasn't been valid for years which is why any dex III branded fluid says compatible with.

IV is a thinner fluid, III starts thicker but both shear to about the same viscosity quick. IV is a more stable fluid period. Hell the turbo 400 I had built game with regular old IV in the box as the reccomended more than good enough fluid.

That being said, there are some certain applications where you shouldn't use IV but none of which are present on this platform.

 

I'll keep tabs on this thread as I'm running Amsoil Signature Series, but having problems and may just redo the filter change and put in a different fluid.

And on the A/C Delco ATF fluids. I believe there are two different kinds. I believe there is a synthetic blend and a full synthetic version. I'm not sure what the difference is between those fluids.

 

As far as my post and recommendation, I wasn't necessarily "pushing" AC delco fluid only! My main point was Dexron VI (6) is safe to use and being recommended for Dexron III applications. Instead of going crazy driving around from store to store trying to find Dex 3, it seems to have disappeared most places over the last year or so! To each their own, I'm not going to tell someone their fluid of choice is crap when I haven't used it, just like if I've had great experience with fluid X, I'm not going to listen to someone talking **** about it👍

 

What's the difference between regular ATF fluid and the "high mileage" fluid? And someone above said they put high mileage ATF fluid in and got some slippage. Has anyone else had that problem? I'd have thought the high mileage stuff would have something in it to help keep it from slipping compared to the regular fluid. I'm deciding what fluid to get as I put Amsoil Signature Series fluid in last year, and I'm seeing a lot of bubbles on the dipstick. And so thinking of redoing the filter and putting new fluid in.

Also, does anyone know of a high quality rubber gasket? I know most gaskets are cork or fiber. Though a decade ago I put on a rubber gasket I think from Frost King. And a decade later I removed it and there was hardly any gasket reside left behind. I probably didn't need to, but I did run a razor blade around the mating surface when cleaning. I do have a Moroso gasket on now that is reusable, though I have bubbles in the fluid and thought of trying just a regular rubber gasket.

Also I saw mentioned on another thread to use a 1/2" pipe to screw into the filter oring that gets left behind in the transmission. Where I guess you screw it into the old oring, and then pull down to remove it. Just saw one guy mention it and thought I'd pass that info along. You can get 1/2" pipe at the hardware store. Though I suggest searching around as I've never done it.

 

Generally, a high mileage atf has different friction modifiers, seal conditioners (or seal swellers depending...) and is a little higher viscosity. As an aside, I don't recall many if any high mileage ATFs carrying an actual license for DEX III (when still licensed) or VI unlike their normal variants... so there is something different enough that it either doesn't meet the requirements, or more likely, companies don't bother to license it for the spec for whatever reason.

 

Like 84 4+3 said there are modifiers that help keep them operating even with looser tolerances. I do want to clarify my earlier post about my problems with the "High Mileage" Valvoline in the burgundy jug. This was used in a fresh built 4L80e not a 700r4. The trans is also modified. I put in a bunch of Sonnex parts along with dual feeding the direct drum. I also installed a shift kit and deleted the accumulators. My line pressure is WAY higher than stock because of the Sonnex valve and spring kit that I put in the pump.

I always liked Valvoline ATF. The price of the "High Mileage" synthetic was a lot lower than other synthetics on the shelf so I tried it. I had two issues the first time I took it out. The 1-2 shift was so hard it felt like a punch to the face. Then I noticed a little slipping under hard acceleration. This happened mostly in 3rd. I remembered a long time ago I had clutch's slip in ATV's with a wet clutch when using some synthetics. So as a last ditch effort before taking the transmission apart yet again I flushed out the high mileage stuff for the synthetic Valvoline in the blue jug. The difference was immediate. The 1-2 shift was much softer and no more slipping.

Maybe it was coincidence. Maybe I had the tolerances a little off and things settled into place. Or maybe the friction modifiers they use in High Mileage ATF doesn't play well with the jacked up line pressure that I have. I can't answer why it caused the issue. I just know it did.

I'm not saying that the high mileage Valvoline synthetic ATF is a bad product. I've used it in lots of transmissions with high mileage and never had an issue. But for whatever reason it gave me issue with this one transmission that was a fresh re-build.

 

Here is the tool. You can see the old seal on the end of the longer pipe. My trans is a 4L60E and I don't know if the seal is the same in yours. Yes, just screw the long pipe into the seal and tap down on the short pipe with a light hammer and it comes right out. Nothing touches the bore. Dan

 

This sure beats the hammer and punch that I use to do this.

 

You really don't even need to make the whole tool. If you just have one pipe then just screw it in and clamp a vise grip on it and tap down on the vise grip. Dan

 

Thanks for clarifying that your issue with the high mileage fluid was in a fresh rebuilt modified transmission, and that you haven't had issues with using that high mileage fluid in other transmissions. I may go with the Valvoline High Mileage fluid. I kind of wonder if maybe the high mileage fluid is a little grippier than regular fluid, as transmissions tend to start slipping as they get older.

https://www.valvoline.com/en/maxlife-multi-vehicle-atf/

 

I've been successful with Valvoline Maxlife in my 4L80 when changed at approx 170,000 miles and it now has 290+K. I've also seen it very highly rated among those who should know.