[Mark G]

Any brand .Any Dex 2 will work don't over think it..

[Chief of the 60's]

LOL @ synthetic

Synthetic is very slippery. Just what you want in an automatic transmission.

I don't know any "quality" tranny builder that would recommend it. Most recommend Type F

[Dragncar]

Originally Posted by Half-Inch Stud

Whatever Red line says is fine by me.

So i'm told Trans Fluid is mineral oil with color and additives for brass/babbit corrosion inhibit, and the "friction modifiers". I use Type-F out of stubborn ignorance, yet at $5.95/QT i'm game to put baby oil in if it were $1/Quart.


If your TH400/4L80 trans fluid goes to 300*F while towing, driving, (or in CLIFF's case while extended Idling (hehehe), then the Clutch Pack Lip Seals will turn into Gummie Bears. A Real mess to clean up.



...extended idling... oh that's funny.

I have serviced large industrial air compressors. They run roots type blowers and mix Dex/Mec tranny fluid with air and use a separator. The dyno fluid only lasts a couple weeks max before its broken down. Used to be a lot a fluid changes. Now they run synthetic and it lasts a good 6 months, but expensive. A 55 gallon drum goes for well over 2,000$. The stuff I have seen is branded "Rodgers" which is a industrial air compressor company. Its clear as can be, looks like baby oil but a little thicker.
I have thought about getting a couple gallons and trying it but never heard of anyone trying it in a T400. Its a direct replacement as far as a air compressor goes and was a godsend as far as maintaining them.

[leeklm]

Originally Posted by Chief of the 60's

LOL @ synthetic



Synthetic is very slippery. Just what you want in an automatic transmission.



I don't know any "quality" tranny builder that would recommend it. Most recommend Type F

I am not in the position to argue your comment, nor do I have enough experience to say one way or the other, but I think most here would consider Jake's to be a quality trans builder- who recommends synthetic in the TH400 they built for me, even after I asked about running non syn or Type F.

Sent from my SM-G965U using Tapatalk

[GreekGTOGT350]

When the Allison transmission was first installed in the GM pickups, GM owned Allison. They insisted within their dealerships to use the TES-295 produced fluid from Castrol called Transynd. As you know it was expensive. GM ultimately sold Allison in 2007, yet continued to install Allison's in their trucks. At that time their dealerships were told to install GM fluid Dex-H, which they had on the shelf. As time went on, they developed Dex VI and that was the new call. All the while this transition was taking place in specifying GM fluids, Allison claimed the best fluid in any Allison was the Transynd spec fluid. Motorhomes, buses and big trucks were told they should have the TES-295 spec or beyond. Castrol would not release the formula to the industry and so different companies either went without or developed fluids by reverse engineering. Amsoil was one of the these companies producing Torque Drive, no better, no worse, yet cheaper. In my Transmission shop we installed a bunch of this fluid and it always shined and did the job even and above the 300 degree mark in trouble situations. I personally use the Torque Drive in my Ford F350 Powerstroke tow vehicle. Great stuff. The pan is always clean and I have all the tricks inside with extra clutch packs and such and Tugger Shift Kit, with pressures turned up.

As a further note on Allison's; they will run on just about any ATF, yet the wear in the valve body and in the clutch packs is so much enhanced with the true synthetic fluids. You don't want to replace one of these trannies.

As for Type F, in Powerglides, TH350, TH400, and the like we would use a synthetic ATF and mix in TYPE F SPEC synthetic fluid called SUPER SHIFT, which can be as a straight type F or mixed in to firm up shifts accordingly. If a guy was high performance (they all claim they are!), I would mix 50 / 50 ratio.

My primary purpose in this forum is my 1964 GTO. Love the Pontiacs. I will mention I am an Amsoil Dealer who works SEMA, PRI and the Mint 400. If I can be of service to you and line you up with a discount account direct, just pm me. Take care.

[Formulajones]

I like the Amsoil products. Been using it for years in engines and diffs.

[78w72]

Originally Posted by Formulajones

I like the Amsoil products. Been using it for years in engines and diffs.

aren't amsoil atf's synthetic?

[Formulajones]

Originally Posted by 78w72

aren't amsoil atf's synthetic?

Yep, I've never tried the Amsoil ATF's though. Been very happy with their engine oil products and rear diff products.

[Chief of the 60's]

SCAmsoil

[78w72]

well since chief has never heard of a company recommend synthetic trans fluid... then thats all that matters & you can never ever use it. ever. end of story. cause chief knows everything about everything! LOL!

[Formulajones]

LOL While I may have agreed with Chief on a couple things in the past, (maybe) when it comes to oil, I tend to only listen to those who bother to send in engine oil samples to form an honest opinion on the oils they are using, their maintenance methods and service intervals. Especially on a website like this where 99% of the people here are lucky to even put 3,000 miles a year on their car, not near enough from a longevity standpoint for oil, and a lot of other things for that matter.

[78w72]

Just gets very old when he posts this kind of stuff with no proof or facts… just that hes never heard of it so it cant possibly be true. A LOT has changed since the 60’s…

Same for the “scamsoil” comments, no proof or credible info at all, just that he thinks it’s a scam so it must be… I think their prices are a little high, but their products are excellent & they are a reputable company that blends their own oils. I highly doubt they would offer a synthetic ATF if it was too “slippery” for a transmission or that Jakes & other companies recommend & use synthetic ATF. Nothing wrong with using a conventional fluid or type F in th400's, but a synthetic fluid will not hurt anything & for many street/daily driven vehicles, it will provide a smoother shift & withstand heat far better.

[Formulajones]

Originally Posted by 78w72

Just gets very old when he posts this kind of stuff with no proof or facts… just that hes never heard of it so it cant possibly be true. A LOT has changed since the 60’s…

Same for the “scamsoil” comments, no proof or credible info at all, just that he thinks it’s a scam so it must be… I think their prices are a little high, but their products are excellent & they are a reputable company that blends their own oils. I highly doubt they would offer a synthetic ATF if it was too “slippery” for a transmission or that Jakes & other companies recommend & use synthetic ATF. Nothing wrong with using a conventional fluid or type F in th400's, but a synthetic fluid will not hurt anything & for many street/daily driven vehicles, it will provide a smoother shift & withstand heat far better.

Agreed, I've met quite a few reputable tranny builders that like using synthetics. I think the "it's too slippery" mentality is a myth. It's in my Duramax Allison trans that sees plenty of towing abuse, recommended by ASE Allsion techs, whom in fact won't warranty their work without it.
Dad's had it in his 400 turbo since it was built more than 5-6 years ago now, with over 700hp/700tq in front of it. Still working just fine, and recommended by the builder who's been in business since 1973.
It may not be for everyone, and I'm not trying to push it, don't care. I still use plain ole dex/merc in 2 other turbo 400's here that work fine too.
I'd like to try Type F in one of them here sometime. Late 80's I bought B&M trick shift for one vehicle, I was told Type F was the same thing, lol.

[78w72]

i used type F back in the 90's in a stock th400 that had a mushy 3rd gear shift, it did firm up the shifts. have a new TCI th400 in my low 11sec firebird & use a regular dex3 compatible fluid & it works great.

i have use valvoline max life FULL SYNTHETIC in a jeep that calls for dex3 for 100k+ miles & lots of towing & it worked great. also use it in my current toyota 4runner 5 speed trans with zero issues & have read numerous reports that maxlife fixed or improved a shudder problem that they are known to have using toyota WS fluid that is not synthetic. amsoil makes a "universal" synthetic fluid that many toyota guys use too.

i agree it may not be for everyone & am not trying to push it. point being, synthetic ATF's have been around & used for a very long time with zero issues & just because one guy hasnt heard of it being recommended does not mean diddly squat.

[Half-Inch Stud]

So Redline has a Rear Gear oil "Sgockproof" that is thin like thinoil or water. The measure of success there is lower Pinion temperatures which you can monitor "before vs after" or crawl under and put you hand on the iron after a sustained highway travel.

The other measure of success is the fluid doesn't turn grayy with steel powders like 80Weight does.

So, if the "synthetic" Trans Fluid does turn gray, and the TH400 pan doesn't get all gray coated, then Synthetic has a measurable improvement.

As for Thermal rise; the Converter dominates with thermal rise from fluid shearbeing physics law. i wonder if trans fluids have a varied thermal rise?

[69 Limelight]

So, does anybody know anything about TCI brand fluid? They have their on formulation, additive package, specifications? Wouldn't think they bottle it themselves. Think the viscosity is more like Dexron III or Type F?

[tjs72lemans]

I was in Walmart yesterday and they actually have Valvoline Dex/Merc. On the container it states "not intended for traditional transmissions". I'm confused. I would consider a '72 turbo 400 traditional. Am I missing something?

[Grand73Am]

Originally Posted by tjs72lemans

I was in Walmart yesterday and they actually have Valvoline Dex/Merc. On the container it states "not intended for traditional transmissions". I'm confused. I would consider a '72 turbo 400 traditional. Am I missing something?

I wonder if they're meaning traditional "manual" transmissions?

[77 TRASHCAN]

Originally Posted by Grand73Am

I wonder if they're meaning traditional "manual" transmissions?

Excellent question.
I worked in a parts tore from 1985-1998. Owner built a new place in 1988, built an oil change into the building. I worked in part store...One day the Lube Goobs (what I called them...) serviced a ford pickup. The pickup had a standard transmission in it. A week or so, later, the transmission takes a dump. It was a F150 pickup, don't remember the engine, BUT the transmission was made by Mazda, took ATF in it, not gear lube. Owner contended we did not check the fluid it it, took us to court, he got a little more than we offered, big whoop. It's possible the Lube Goobs didn't check the fluid level, but it was the first I had heard of a manual trans having ATF in it. Sound logical, a low viscosity fluid, much less drag than gear oil. If a trans was engineered for such a fluid....I wouldn't want such a trans, though...........

[Formulajones]

Originally Posted by tjs72lemans

I was in Walmart yesterday and they actually have Valvoline Dex/Merc. On the container it states "not intended for traditional transmissions". I'm confused. I would consider a '72 turbo 400 traditional. Am I missing something?

LOL, I'm old school too so when I hear traditional first thing I think of is 50 year old 400 turbo

Not really sure what they mean by that these days, but I have Valvoline Dex/Merc on the shelf. I'll go take a look and see because I've never noticed that before. I'm using it in 2 400 turbos here though and have been for years since Dex II and III have been obsolete.

Not related but since the subject came up on the manual tranny deal, I have 2 modern 5 speeds that are engineered for very thin oil. Some people just run ATF. Both the TKO and the T5 come with specific requirements in the paperwork. In the TKO I run Pennzoil syncromesh (it was one of the recommendations) and it's a very thin oil, pours almost like ATF. In the T5 I'm using Amsoils syncromesh and again it pours extremely thin. Made specifically for todays manual transmissions. The Amsoil is synthetic, and I believe the Pennzoil is not. Both trannies shift very nice.