Powerglides & Slim-Jims

[Joe C.]

When I harken back to the early sixties, I can remember only two kinds of ATF: Type F, and Dexron. The Type F was used for "Fix Or Replace Dailys"; the Dexron was used for Mopars. I am not sure about the Powerglides and Slim Jim's, but they probably also used type F. Chrysler, who was always on the cutting edge, was probably the first to use Dexron.
Now, type F is just about a dead issue for most cars. But I am confused about Dexron II, Dexron III, Mercon, and Mercon V.
My '85 with 700R4 requires Dexron II ATF, and lo and behold, I just happen to have 4 quarts of Valvoline Dexron II on hand........just what the doctor ordered. I 'll still be 1 maybe 2 pints short. I no longer see any Dexron II on the shelves out there. All I can find is Dexron III/Mercon, and Dexron III/Mercon V. Are all these designations just marketing crap. Are they suitable and compatible with the good ole' Dexron II?

Joe

[Joe L.]

Re: Powerglides & Slim-Jims

Joe-----

They're not just marketing terms. There is a functionality issue. However, the Dexron II and Dexron III are fully compatible, so you should have no probelms, at all, if you mix them.

I do not recall, however, that Dexron was used in the 60s or by Chrysler. I thought that Dexron was a GM-proprietary term and came along well after the 60s. However, I've never been very much into automatic transmissions so I may have "missed something". (I like automatic transmissions now, though; yes, indeed.)

[frank mccracken]

Re: Powerglides & Slim-Jims

Back then Fords and Chryslers got Type F, GM's got Dexron. Now I think the trans shops have a really big tank of one kind for all.

[Joe C.]

Re: Powerglides & Slim-Jims

Joe

You jogged my memory, and I seem to remember a Type A fluid, which was used, probably by GM, early on. Type F AFAIK, was always used by Ford (Fordomatic/Mercomatic/Cruiseomatic). Early Chrysler Torque Command trannys and PG/Slim Jims likely used Type A. Not sure about Rambler's Flash-O Matic, but probably also Type A.
There are so many "designations" to keep track of. To simplify, just eliminate Type A, and Type F from modern terminology. Now I am only trying to determine the compatibility of Mercon, and Dexron.
There may have been a point in time when all ATFs were standardized, because it seems that Dexron/DexronII/DexronIII/Mercon/MerconV will work with any auto trans for the last 20 years.

Joe

[Joe L.]

Re: Powerglides & Slim-Jims

Joe-----

Yes, the "Type A" fluid was the old designation. From what I can tell, the new name was adopted about 1969. However, at first GM listed it as "Dextron". Sometime later, the "t" was dropped and it became "Dexron". For several years beginning in 1969 it was listed as "Type A (Dextron)". Later, the "Type A" was dropped entirely and it became "Dextron" and, then, "Dexron".

[Mike M.]

Re: Powerglides & Slim-Jims

Joe,
If I remember things correctly, type A began to be replaced about the time the whale oil was removed from ATF (remember the GM problems with "rusting tranmissions"?).
As I understood it, type F was less "slippery" than Dexron or Type A. This was due to Ford AT's using fewer or smaller clutch plates per given application than the other manufacturers. I do know that we could always replace the type A or Dexron in a GM Tx with Type F and get firmer shifts.

Mike

[Michael H.]

Re: Powerglides & Slim-Jims

The "Slim Jim" (Roto Hydra-Matic) was the very first automatic transmission I ever overhauled in the 60's. What a terrible unit but fun to work on. Three speed, none of which were good for anything.

I believe Joe Lucia and Mike McCormick have it right. I remember "Type A" was used for everything until the late 60's. I thought the high friction oil was used on late 60's Fords?? We used to use it in GM cars for a firmer shift.

[Clare Carpenter]

Sperm Whale oil

Sperm whale oil was so effective that auto trannies and posi rear ends didn't need to have their fluids changed over their service life. In 1972 the Endangered Species Act outlawed the killing or the use of materials derived from whales. For a while after, substitutes were nowhere near as effective and early failure was often the result. However, today's wax esters, derived from Flaxseed are as good, if not better than whale oil though periodic changing is required.

The link below (if it works) is a good article on the history of OEM brand auto trans differentiation and development of new base stock.

http://www.atsgmiami.com/articles/html/TD%2011_04%20Shift%20Pointers/TD%2011_04%20Shift%20Pointers.htm

[Joe C.]

Re: Powerglides & Slim-Jims

Yes, they were very weak units. Any Pontiac with a torquey engine would burn the POS out in no time.
Speaking of old transmissions, was it Buick with the Dynaflow, and Olds with the Hydra-Matic, or vice versa?

[Michael H.]

Re: Powerglides & Slim-Jims

Yep, was Buick that had the one speed wonder, Dynaflow. Boring ride because they never shifetd. Instead, they used a variable pitch stator in the convertor. Pontiac and Olds first had the 4-speed Dual Range Hydra-Matic, later replaced in the late 50's by the 4-speed Jet-A-Way Hydra-Matic. Dual Range was a popular unit for drag cars in the early/mid 60's. I've built a bunch of those for racing. Problem was, they weighed as much as the whole rest of the car. When the T-400 came out in the early 60's, the old Jet-A-Way's were discarded. 40 years later, the T-400 is still my favorite unit.

[Chuck R.]

Re: Ahh Joe you bring back memorys

I fondly remember the Plymouth commercial where the spokesman was touting the "Torqueflite" transmissions and how dependable they where, while in the background a Satelite was smoking the rears off slamming it from D to R

I was so impressed that I took my Dad's Grand Fury out on Oak Grove Hill and let her have it!

My only small problem was that I blew one of those fabulous steel belted radials and tore up the side skirt and wheel well molding

That tranny took everything I could throw at it and then some, so I'll vouch for the type F

Chuck

[William C.]

Re: Ahh Joe you bring back memorys

I have different memories of the Torqueflite, I remember a problem where a sprag in an overrunning clutch would fail and those boys would explode with all the shrapnel of a hand grenade at the drags. I had one (426 wedge car) do it right in front of me right before the starting line at Natioanl Trails outside Columbus. Quite a Mess!

[Dick W.]

Re: Ahh Joe you bring back memorys

The A-727 Torqueflight was a very stout transmission when built properly. It could stand the hp and torque of a built 426 Hemi. The weakest point was the reverse band. It would not stand much when you were rolling forward and put it in reverse. It would snap the band

[Mike M.]

Re: Powerglides & Slim-Jims

Joe,
Yes, Dynaflow was Buick and Hydramatic Cad, Pontiac and Olds. EXCEPT when the Hydramatic plant caught fire and was nearly destroyed ('53? '54?). Then Cads received Dynaflows and Pontiacs got Powerglides for a short period of time. I think what Hydramatic production remained went into Olds, but maybe they got Dynaflows too.
Michael H., I just got a '59 Dual Range Hydro. One of the last produced and out of a '59 Cad hearse. I think they were only used in the commerical chassis, rest got the Jetaway (Cushion Coupling). Don't know what I'll ever do with it (long tailshaft version) but never pass up a freebe.
Mike

[Dick W.]

Re: Powerglides & Slim-Jims

Do I see a 50's vintage drag car in the making? You just need a few more pieces and you are ready to blast down the strip