72polarbear
New Member
finally ready to put fluid in my freshly installed 727 rebuilt nearly stock so just wondering what you guys would recommend and what’s the procedure to start up. Thanks
A-727 swap to 360 what trans fluid recommendation.
- Thread starter 72polarbear
- Start date
bronze turbine
Active Member
MoPar ATF +4 would be the best ATF to use.
1970FuryConv
Old Man with a Hat
Dexron 3 was factory recommended in 1972. I have used Dexron 3 with good performance in a 1968 727 that I rebuilt. It's behind a 1969 440.
You will pay more for ATF+4, although it's fine for your car.
Viscosity loss (20 hour KRL Shear test) Dexron-3 40%, ATF+4 10%. Dexron-3 = garbage.
1970FuryConv
Old Man with a Hat
-In other words, you are saying that Chrysler recommended customers put garbage in Chrysler transmissions?
-If that's the case, how did our cars survive in the 1960s and 1970s under high stress Police use? NASCAR? NHRA?
-ATF+2 did not become available until 1980, how did our cars survive until then?
Where are you getting these statistics? Link to article or actual test report?
By contrast, here's an email from Richard Ehrenberg, Tech Editor for Mopar Action Magazine. I wrote regarding trans oil for a 1990 pickup.
Note: lockup trans were not in production until 1979 and do not apply to 1972 Polara.
Date: 2/8/2010 10:29:41 PM Eastern Standard Time
From: tech@richardehrenberg.com (Rick Ehrenberg)
To: my email
"The only issue with Dexron is possible lockup shudder. Other than that, Type
F is really the way to go. Personally, I'd try the el Cheapo gallon jug
Wal-Mart juice. No possible harm, just the shudder - a 25% chance of that.
And there's a good chance that your '90 518 isn't even lockup.
ATF+4 is really good stuff - synthetic. Wal-Mart does have that, too."
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Non-lockup torque convertors are heat pumps and they heat and shear the transmission fluid quite a bit, way more than the lockup converters that came in the 80's. ATF has long been formulated exclusively for transmissions with lockup converters.
Thing is, the performance degredation in ATF is not noticable. Your car will still move after 20, 30, 40 k miles, but I bet the change in the stall speed and input/output RPM difference is measurable vs when the oil was new.
What's interesting is that I look at my '67 factory service manual, at the maintenance and lubrication section, where they show what to do at X months or X miles, and it only goes out to 3 years / 36k miles. Change engine oil every 3 months or 4k miles. Transmission fluid? Nothing. Just keep it topped up, but no scheduled changes out to 3 years or 36k miles. Maybe because at some point you had a transmission problem and in your city there was a transmission shop on every block, and any service required dumping the fluid anyways?
bronze turbine
Active Member
I believe severe service recommendation (police, taxi, etc.) from Chrysler back in '72 when Dexron III was in use was to change it every 30,000 miles. It's not going to kill you're transmission to use it, but it is 50-year old technology. To be honest, if it's going in a classic car that only gets driven minimally, Dexron III would be fine. If I was going to be daily driving it, I'd use the ATF +4. But still, if it's a classic car driven minimally, you are probably not going to be going through gallons of fluid, so why not just spend the few extra bucks and get the better product.
bronze turbine
Active Member
Maybe instead of arguing about the fluid, maybe someone could address the OP's question about starting up the transmission. I'm curious about this myself, I've never started up a rebuilt transmission. Any special procedures?
1970FuryConv
Old Man with a Hat
KRL (Tapered Roller Bearing)
The KRL shear test uses a tapered rolling bearing in a cup fitted to a four ball instrument. Load is applied to the bearings as they are rotated at a certain RPM for a specified length of time. The test is typically run for 20 hours. KRL is considered to be one of the most severe shear tests and is used for driveline fluids and gear lubricants.
Shear Stability and Viscosity Loss - Savant Labs
Shear stability is an important aspect of lubrication. Most multigrade lubricants are formulated with viscosity modifiers in order to increase the viscosity
www.savantlab.com
My question: How many C-bodies are driven 20 hours at a time under severe loading? Dexron is fine if used under normal driving conditions. Chrysler engineering is excellent and our transmissions were engineered for use with Dexron. If you want to spend more for ATF+4, up to you. I have been over 100 mph with Dexron in a 727 that I rebuilt. No problems.
@72polarbear
*I poured 1 qt in Torque Converter. Requires pouring very slow. I installed the torque converter on the trans and then installed the 727. Since you trans is already installed, I can only hope you did this. If not, I would keep the engine at low rpm so front pump has time to fill torque converter before any overheating.
*I added 2.5qts in OEM trans pan [3.5 quarts with deep pan] I did this because, if you add all fluid at once, you can have fluid aeration from rotating parts hitting the fluid before it is distributed throughout the transmission and you can submerge the valve body.
*I started in Neutral
*I filled by adding 3.5 more quarts
*I watched dipstick and added another quart after trans heated up
*My rebuilt 727 trans took 16 quarts total
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Whiskytango
Member
As a precaution I always put stands to lift rear wheels off ground. Seen a few vehicles where linkage wasnt set right and tranny engaged in drive or reverse as it filled with fluid. You can also run it through the gears with wheels off ground. Just make sure wheels have come to complete stop before shifting into reverse or park.
wyrmrider
Member
DEX III is no longer supported by gm so quality now varies all over the place unless you get the Allison Certified part number
Never use DEX VI or universal unknown
ATF+4 is great as it is synthetic blend and very cost effective (however cost of full synthetic has come down since ATF III 4+)
Gil Younger at Transgo (my late friend my shop was just around the corner from them) said NEVER run type F except where specified it is sometimes not compatible with some seals and clutch facings shifts too hard so hard on bands and clutches what to shift hard adjust your shift kit
ABSOLUTE BEST is CITGO QUATROSYN full synthetic no shear down best cold like for snowplows AND best hot (also snowplows but HD use) Longest Lasting Best overall costs in My fleet tests with analysis dOES NOT THIN DOWN
not only for Allison but works in everything (like Nissan, Honda Toyota )
EXCEPT Where type F or CVT
There is no more whale oil or Type A for those fluid drive users
Never use DEX VI or universal unknown
ATF+4 is great as it is synthetic blend and very cost effective (however cost of full synthetic has come down since ATF III 4+)
Gil Younger at Transgo (my late friend my shop was just around the corner from them) said NEVER run type F except where specified it is sometimes not compatible with some seals and clutch facings shifts too hard so hard on bands and clutches what to shift hard adjust your shift kit
ABSOLUTE BEST is CITGO QUATROSYN full synthetic no shear down best cold like for snowplows AND best hot (also snowplows but HD use) Longest Lasting Best overall costs in My fleet tests with analysis dOES NOT THIN DOWN
not only for Allison but works in everything (like Nissan, Honda Toyota )
EXCEPT Where type F or CVT
There is no more whale oil or Type A for those fluid drive users
It would be useful, and maybe it is done but I doubt it, that someone gets used trans oil analysis like they do for engine oil. It might tell us what's happening to these oils as they age. Then we'd have something really to talk about when it comes to this or that oil and how it thins or breaks down in our 727's.
The problem with Citgo Quatrosyn is that I can't find any hint that they are certified or meet Allison TES-295 or even TES-389 specs, or any published results for the KRL 20-hour shear test. But then again I don't see where ATF+4 stands on the Allison specs but at least there's the KRL shear test.
According to Ai searches, the 4-speed Allison AT545 transmission has a non-lockup torque converter (and no over-drive) and is used in school buses and is otherwise designed for smooth comfortable operation. It might be or is superseded by the MT634 with lock-up converter. So the fluid requirements of the AT545 might be the most similar to the 727 today.
Regarding the AT545, Ai says this:
============
For the Allison AT545 transmission, the top recommendation is a synthetic Allison TES-295 or the newer TES-668 fluid (such as Castrol TranSynd) for superior high-temperature protection. While originally designed for DEXRON-III, modern synthetic fluids are preferred to prevent overheating, especially in applications lacking a lockup torque converter.
============
They talk about trans fluid like it's engine coolant, and the Ai bots focus on advertising lingo. Trans fluid isin't going to "protect" anything from overheating, not with the pidly heat exchanger in the rad. Now whether some fluids can handle hotter for longer, that's what's at stake here.
And yes I asked, and the answer is that ATF+4 does not meet TES 295 or 668 specs. Citgo says Quatrosyn can be used where TES 295 is specified, but Quatrosyn does not hold formal approval for 295 or 668. AI goes on to say that Citgo recently released a different product - CITGO SynDurance 668 ATF - which is officially approved by Allison for TES-668 and is backward compatible with TES-295.
The application for the Syndurance is written as "Vocational vehicles in severe duty, stop-and-go conditions; suitable for on-highway and off-road applications requiring TES 668". Again, vocational vehicles where perhaps a smooth transition between gears is required.
(That got me thinking about this. I'm almost always the driver in any car I happen to find myself in - which is usually my cars. If I'm a passenger, which I rarely ever are, and the drive is long enough, usually in a city / urban situation, I will get car sick. Something to do with gear shifting maybe?).
Other oils meeting TES-668 are Delo Syn ATF 668, Mobil Delvac 1 ATF 668, and Castrol TranSynd 668.
Again according to AI, ATF+4 does not meet any Allison transmission specifications (maybe it's never been tested for such) while Dexron III does meet Allison C4 (but C4 is old/crappy spec) and can meet TES 389 specs (which largely have to do with compatibility with Viton seals used in or before 2007). TES 389 is far inferior to 295 specs.
This document might have some useful tidbits of info on this topic of oil:
https://www.infineuminsight.com/media/1820/9-power-transmission-fluids-na.pdf
Note page 8 (ATF requirements), page 9 (torque converter clutches - BUT THE 727 HAS NONE!), page 10 (torque converter - large energy loss without clutch!).
Page 14 (shear stability chart, ATF+4 not shown for some reason)
My take-away is that ATF+4 was engineered first and foremost to prevent torque converter lock-up clutch chatter 25 years ago in MoPar auto transmissions. Our 727's don't benefit or care about that. But ATF+4 base oil seems to be way better than Dexron III so that's something the 727 can use.
I am curious now about the oils meeting TES 295 and 668 specs and they are likely better than ATF+4 in terms of shear stability (heat tolerance, oxidation). Citgo Quatrosyn is still an unknown in this regard.
1 gallon jugs of Citgo Syndurance 668 seems to retail for $45, and you'd need 3 for a full 727 oil change (with 2/3 of a jug left over). Castrol TranSynd 668 runs $60 / gallon (ouch). Valvoline Dex/Merc Dexron III-H gallon jugs run $36.
And maybe we can do better for our cars by adding a trans fluid cooler?
lemondana
Active Member
I've been using Type F in every 904 and 727 I've ever owned for just about 50 years. Never had a trans failure.
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