GM Automatic Transmission Fluid - ATF History Part 2

[@nhra7110]

Thank you so much for this truly awesome video on the GM history, Prof. Kelly! Your knowledge, collection of the old fluids, AND many of the transmission models themselves I bet is among the best in the world - incredible. Would love to be able to see and study them more in person:-). Those 2nd and 3rd gen Hydramatics from the late 50s early 60's were bizarre designs indeed. Can't wait for the next videos!

[@WeberAuto]

Thank you very much. It has been fun to learn about them

[@karlitaaguirre3116]

Eclipse

[@Blue_band4516]

P PPP go

[@chris.nragsdale7841]

Ookoooookioookioookiok ookioiolookook ookookilioioikook oòkiookikkook kok iook ok ookioookok ioook kok ioikok iokiiiiI'll iookiiiiill ookiiiiok ioikok ioioikiook iook ioI'll iikook ioioikok oko

[@mistakane]

😘😘😘😘❤️❤️😘🎉😀💍😭😘😀💍😘😂😂🙏🙏😭🙏🙏🔥🔥🔥🔥😭💍🎉🎉🎉💍💍💍🔥🙏💍

[@sleepwalker8600]

This man is the most knowledgeable man on general motor vehicle technology I’ve come across on the internet and in real life in the trade. The depth of not only knowledge but understanding is hugely impressive. I bet all his students keep him on speed dial for life.

[@madintheheid]

A masterpiece in lecture delivery, which showed why, if you find something you're good at and you live, you'll never 'work' a day in your life!

[@compu85]

One take away I have from this series is just how much engineering and design goes into every part of a car... even the “simple” fluids!

[@deanmason1564]

It's like going back in time! 😉

[@ml.2770]

Prof. Kelly you are a KZbin treasure. Thank you for the great videos. I always buy original Warco automatic transmission fluid.

[@WeberAuto]

Thank you! Stay away from Warco ;)

[@HobbyOrganist]

Original FAKE certified Warco with the patent that is for the CAN only LOL, :)

[@dkaloupis75]

Click the "thanks" button then.

[@billynomates920]

i like that when he talks about the transmissions, he reaches out and puts his hand on the transmission.

[@AustinLeeds]

I just watched a 90 minute video on transmission fluid. And I liked it.

[@WeberAuto]

LOL! Awesome!

[@paulsim24]

Me too! I must be getting old!

[@24100mw]

Professor Kelly, I watch a lot of KZbin videos and this presentation was by far the best I have ever watched, it was professional from start to finish and you did it all with no ego involved. I look forward to watching many more of your instruction videos. I have a new purchase to me in 2023, a cherry 2019 Corvette Z06 with only 3500 miles on it and I have an appointment to get the trans flushed tomorrow. Now I know all the questions to ask, thank you.

[@bowtieguy6870]

Wow, unbelievable amount of time and effort put into this. Thank you very much! Absolutely outstanding work.

[@WeberAuto]

Thank you!

[@dkaloupis75]

Click the "thanks" button then for the outstanding work.

[@regthebackyardjackofalltrades]

Thank you for reminding me. I totally forgot about the traction control system switch. No one was prepared for this snowstorm and I had tunnel vision at the time. Maybe the other vehicles were stuck because they didn’t turn off their traction control. The best thing that came from the snowstorm is that I had 13.5hrs of “Quality Father and Daughter Time...” that I will always remember. You are one of the best professors out there. Your information is keeping me busy and learning which makes my children think that I’m one of the smartest Dad’s in the world...

[@WeberAuto]

Awesome, I am glad to help.

[@GammaCruxis]

Absolutely fantastic! Well done and very informative. You are definitely a gear head, and your love of it shows. This makes it all the more enjoyable. Can’t wait to see the next one. Cheers!

[@WeberAuto]

Thank you

[@Gordonseries385]

Just an tool time type of guy, I always spent a lot of time looking and reading when it came to transmission fluid. Really apricate your efforts, great job on your presentation! Retired and 15 plus years not working on cars, my guess was wrong thinking that it would get simpler as technology move on. Enjoyed your video and learning the new advancements in the auto industry.

[@WeberAuto]

Thank you very much!

[@glenngoodale1709]

I always feel lucky to have learned from your video's ! Very thorough and satisfying !

[@WeberAuto]

Thank you

[@David-ik8wj]

i am 56 years old and up to the minute i watched this video, i always called it DEX~TRON fluid. I owned Ford vehicles in my early wrench it myself days so never really put my hands on a can of GM fluid. Gosh...you learn something new every day. is it common to mis pronounce that name? I own a Pacifica PHV and really enjoyed learning how its drivetrain works. You are a master of your profession. I hope Weber takes good care of you.

[@garyrobinson3735]

I run a small shop. Information like the wonderful content you've provided here and in other videos really helps to answer my customers questions about Automatic Transmissions. Thank You Professor Kelly.

[@WeberAuto]

Thank you, I am glad it is helpful

[@jkline3647]

I very much enjoyed this historical look at transmission fluids. I was a Buick tech in the 1960's and 70's when Buick introduced the Super Turbine 400 transmission (in 1964). Buick designed and developed the ST400 and after the 1964 model year the transmission was "corporatized" and given over to the other divisions. Its manufacture was then turned over to the Hydramatic Division of GM and became the Turbo Hydramatic 400. The original Dexron fluid contained whale oil (I think to control certain types of corrosion). Later when there was a world-wide ban on the hunting of sperm whales, GM removed the whale oil and reformulated the Dexron fluid. What GM didn't realize was that the new formulation contained chemicals that attacked the solder in the radiator oil coolers and resulted in engine coolant entering the transmission, and transmission oil entering the engine coolant. Needless to say the coolant ruined the transmissions and required full overhauls (or replacements) under warranty. Additionally, the chemicals attacked the metals used in the transmission thrust washers and resulted in failure of those. This was when GM started to use plastic thrust washers in light thrust locations and Torrington needle thrust bearings in more heavily loaded areas. As you might imagine, this was a very expensive warranty expenditure period for the General.

[@jimgrazulis3542]

I remember the whale oil used in the GM transmission fluid. I thought it was good "for life" fluid in ST/TH400 util it was changed when the whale oil was banned.

[@cowboydan86]

I must be a gear head because I was excited as well a out the oils. Your videos are amazing. I can watch them for days your wealth of knowledge is amazing. Great job sir thank you for your time and effort in helping gear heads like us.

[@133dave133]

Very interesting! I only made it through half way for now (4am), but I'm looking forward to watching the rest tomorrow, and all of the other videos coming. Thanks!!

[@WeberAuto]

Thank you!

[@cryalowicki]

A deep dive like only you can do Professor Kelly. You are a value to the automotive community. Thank you for sharing.

[@WeberAuto]

Thank you very much!

[@brianalbrecht4423]

Unbelivable work...! Never saw so much information on automatic trans fluid & automatic trans history....! Thank u for all the hours,days,years of garathering this wealth of information....bravo....!

[@a_monkie]

i would love to see a video like this for Coolant/Antifreeze! there is a lot going on with different standards, and im sure you could make it an awesome video!

[@WeberAuto]

Thank you! That would be interesting

[@bigqueue]

Professor Kelly....you are clearly trained as an instructor, because you bring this information together in a wonderful visual package that is very informative with all the back-up reference data! Excellent work!!!

[@zynzy4u]

Your informational videos are literally the very best and most factual have ever seen. People say and video all kinds of false information which you seem to be on the very opposite end of. Without exception, your work is brilliantly accurate and extremely informative. You do the world a great service!

[@volvo09]

Stunning history given! Even back in the day there were "a million" types of transmission fluid! Haha! Cool can collection too, love the full ones :) I cannot wait for more!

[@WeberAuto]

Thank you very much!

[@hurricane-gargoyles-warrob5193]

I don’t know how I happened upon your channel, but I glad I did. I’m not a Motörhead, but I find your shows very interesting and I can feel your passion.

[@agtpony]

Incredibly informational you have literally answered every question I've ever had about transmission fluid it is always been such a mystery

[@WeberAuto]

Awesome!

[@bigbill2376]

Wow. I have no real use for this info other than being an average joe/backyard mechanic but I became so enthralled with this information I ended up watching the entire video with great interest! Thank you ever so much for this information!

[@stevepeluso911]

Lots of awesome info here. Being a trans rebuilder for 40+ years and specializing in vintage transmissions, I do have a few small disagreements, but it doesn't amount to very much! I'm looking forward to watching more of your videos!

[@WeberAuto]

Thank you! I am sure I made some mistakes

[@stevepeluso911]

@@WeberAuto, they were small potatoes. Like the years that a certain transmission was in production. A Cast Iron Dynaflow never upshifted. They did have variable Pitch after 1955. Dual Coupling Hydramatic was introduced in 1956. Roto Hydramatic did not have a Variable Pitch. Iron Power Glide ended in 1962. I learned quite a bit from your video and I watched it right through. If I can offer you any assistance, please let me know. Congratulations!

[@WeberAuto]

Thank you!

[@WeberAuto]

@@stevepeluso911 Thanks again, I appreciate the feedback

[@howardhagadorn9443]

I found your videos after watching a guy disassemble a 50 Olds Hydramatic. I have a 52 Olds Super 88 w/ hydramatic and my buddy told me I could use Dexron lll and I've been trying to verify. I'm also having a problem with reverse lockup pawl engaging when I'm trying to back up and wondered if that had to do with the fluid. Your video was very long and a couple of the others I've watched on the hydramatic weren't exactly short, but I've definitely learned a lot of stuff. But geeeeez man, it's almost 8am and I haven't been to bed yet lol And now I see there are so many more videos for me to watch. Keep up the good work

[@WeberAuto]

Thank you. The fluid should not affect the reverse pawl. Dexron-III(H) is your best bet.

[@geralderdek282]

Thanks for a super informative and interesting video! I remember warco fluids and being told to steer clear of it. I brought my '59 Ambassador to my high school auto shop in 1974 to change its trans. fluid. I used Quakerstate type a suffix a and remember the strong order it had which told you it was not like motor oil. Ironically it started shifting erratically afterwards. Was fine before that! My instructor told us that a.t.f. had very high detergent content and loosend up deposits. I did not remove the pan and change the filter. Live and learn!.

[@lasithrajamanthri5992]

big salute for you Prof. What a tremendous effort you done to make this video. A university grade lecture and it’s free. Legends like you still lives that we can have faith in humanity

[@WeberAuto]

Thank you very much!

[@unclemarksdiyauto]

Very interesting video. Will be looking forward to the other trans oil videos, Ford, dodge, and Toyota. Thanks for all the research prof Kelly!

[@Southernshaker]

Your the best, can't believe four people didn't like this.

[@WeberAuto]

Thank you! I was thinking the same thing about the dislikes

[@regthebackyardjackofalltrades]

Great Information. Last week I drove from New Jersey to Norfolk with my daughter and got caught in the snowstorm. I was driving her 2014 Ford Focus. I was following a Tractor Trailer which was paving the way for me until the snow got too high and her car got stuck. I tried to "Rock the Car" back and fourth but I wasn't used to the new transmissions that didn't grip the snow. Maybe I didn't feel it shifting but since I moved to California I never thought that I would get caught in a snow storm again. I was able to rock the car very slowly and reversed out of the high part of the snow to the well driven path and stayed in the "conga Line" for 13hrs. I definitely would've like to have that old transmission last week.

[@WeberAuto]

Sorry to hear that. Some vehicles allow you to turn off the traction control to get better response on road surfaces like that. Thanks for sharing!

[@Hutch_moto]

Great tech. Really enjoyed and am now educacated , as a small engine mechanic by profession , and automotive mechanic and info hobbyist I really enjoy all your deep tech . There's not many automotive repairs I will not tackle on my own vehicles ,the added pressure of someone else's time and money at stake is what defines a professional automotive technician I suppose , perhaps if I had not been a under achiever in my younger years I would have liked to been in the automotive tech industry . Anyhow Take care

[@scottmarshall6766]

What a tremendous undertaking. You executed it with distinction and confidence. This is without a doubt the most detailed and thorough examination of any aspect of mechanical evolution I have ever seen. I can't imagine the hours of research you put into this. I'm somewhat a GM history buff, but learned so much here I'm completely amazed. I didn't think anyone anywhere had an understanding of this sort of history on the level you present so beautifully here. I've been watching your videos for the last few weeks, having discovered them just recently, and have not been disappointed by any of them. This one stands out as truly a work of art. I am now a sub, and will be visiting your Patreon site. If I ever run across a can of Dexron IIE, I'll be sending it to you. I'm looking forward to the rest of the series, and to following along the rest of your videos. Between Paul Danner's work and yours, I feel as though I am going to college all over again. I wish my college age sons had attended your school. Really good teachers are rare, because it's much harder to teach a subject than to understand it. You transmit that understanding efficiently and in an entertaining manner. I remember what I have learned from you. Thanks Professor!

[@ZZZZ-wz4ue]

Again, he keeps referring to the Dynaflow transmission, which was used as an actual tank transmission in wwII as apposed to the just the engines from cadillac and oldsmobile. The dynaflow used no gears and thus in not a " 2 Speed " transmission as the pontificator asserts. It is a 2-range automatic transmission. The ranges of Drive or Low are the result of different movements of the Stator Vanes thus producing less or more fluid pressure operated via pumps and couplers. It had variable pitch vanes. The hydramatic transmission was huge due to the fact it was actually a standard transmission inside with a lay shaft of gears and the resulting jerking that would be felt as the transmission shifted to an actual gear set 1-4 would result. The Dynaflow however not having any gears offered completely free ascending speeds without any sensation of shifting of gears as there were no gears to shift. This dynaflow design operated much as CV vehicles do today. Many actual experts proclaim the design of the Dynaflow as the first real automatic transmission. It eliminated not only the clutch and manual shifting but also the jerking of gear set changes as speeds changed. Buick used it from 1948 thru to 1964/65 with many improvements along the way.

[@roncav53]

Your the Best Prof. Kelly.,,,You go Above and Beyond the Stratos.

[@WeberAuto]

Thank you!

[@jpf6133]

Brilliant and Exceptional research and presentation. Thank you for your effort and hard work it is inspiring.

[@WeberAuto]

Thank you

[@wysetech2000]

That was excellent! Thanks for all of the effort and research put into this video.

[@WeberAuto]

Thank you!

[@DEW409]

Fantastic history. I salute you for the incredible amount of research you had to do to produce this video. My history with GM automatics goes back to the dual coupling 4 speed hydramatic. Things sure have gotten complicated since then.

[@WeberAuto]

Thank you, it was a lot of fun

[@mann_idonotreadreplies]

@dew I find the older design more complicated.

[@MrYAMAHA32177]

Wow, that's a lot of information and more than I would have ever thought about fluids, thanks again.

[@WeberAuto]

Good to hear

[@tomhabrzyk619]

amazing content. really appreciate your time into the research. too many people today proclaim to be experts... with nothing else but a keyboard in front of them. as a fellow gearhead i recommend your videos to many. please keep up the good work!

[@jasonma7578]

VERY GOOD JOHN THANK YOU FOR ALL YOUR HARD WORK AAÀAAAA !!!!!!

[@seanonearth]

I really enjoyed this! Thank you Professor Kelly!

[@WeberAuto]

Thank you

[@19553129]

Thanks. Professor Kelly some great information.

[@WeberAuto]

Thank you!

[@nitro105]

I think your videos on the operation of transmissions particularly the old ones to be very interesting, Thank you for your work.

[@josephgalvin6218]

Love the info so much had changed and very good job at finding all the show and tell pieces enjoy all thifo you give thank you to your school and you professor kelly!

[@WeberAuto]

Thank you!

[@nickmayo2974]

Thanks for sharing your knowledge! Fascinating stuff!

[@WeberAuto]

Thank you

[@magicsenior4185]

You deserve an Oscar and money I am 67 years old still playing catch-up w ith all that

[@indikesamarakoon7723]

thanks a lot , I would gratitude you for what you gave us and for your effort on behalf of us !

[@WeberAuto]

Thank you very much

[@brianhaygood183]

Wow. I really appreciate all the research you've put into this. Thanks.

[@scottschroeder4131]

Excellent and thorough! I can't wait for your Mopar installment.

[@WeberAuto]

Thank you!

[@richardprice5978]

something stupid of me but i hurd that prier to 1970 wale oil was used for automatic transmissions wether that's true or not i don't know because im not " a old timer " ( a hint i came in to this world after the gm 700R4 was in mainstream use but before the 6l80E ) and maybe it's a wise tail that the older baby boomers coworker mechanics told me

[@KieNjiru]

I've learnt so much. Got to watch this a few more times

[@WeberAuto]

Thank you very much

[@Ariccio123]

Amazing content as always!

[@WeberAuto]

Thank you!

[@gerardcousineau3478]

Excellent 👌 subject of history. I had seven of those transmissions. Never heard of the transmission without the shifting feel before today. My dad had a 1960 Pontiac station wagon I think it was the 2 speed in it. It was blue and quite cute.

[@pmcdermo1981]

Amazing video. Extremely interesting, thank you very much for all of your hard work.

[@UKSCIENCEORG]

This is exceptional. Many thanks for all your very hard work Professor.

[@WeberAuto]

Thank you very much!

[@TruthPoliceLegend]

The Turboglide was Designed and promoted by Frank Winchell-a later GM Vice President. I had the honor to work as a technician with him when GM brought him back from retirement as an engineering consultant in the late 1980s at the GM Proving Ground on a brakes project.

[@chasa4347]

Wow - I've got a genII Volt, and when it comes time to change out the fluid, I'll know what to use!!! thanks professor for the instruction! (I need to swing by Weber and see what is new, I attended in the 76-77 years)

[@dexol4784]

Awesome video as usual with Prof. Kelly ..... thanks a lot

[@ozzstars_cars]

Thanks for sharing your knowledge.

[@scottjacobsen4961]

On edible body of research! Thoroughly enjoying all your videos

[@WeberAuto]

Thank you very much

[@randybills3848]

Very cool I cant believe the things I didnt know after 55 years of driving and claiming to be somewhat of a gearhead BIG car nut very interesting thanks so much

[@arquiJ]

Great work! Thank you, from Brazil.

[@eatingplaydoh]

Amazing job sir!

[@WeberAuto]

Thank you!

[@moclepocle]

This is a really excellent video. Thank you for your experience.

[@WeberAuto]

Thank you

[@HobbyOrganist]

That was an outstanding, interesting, well put together video by Professor Kelly! I had NO idea the fluid was changed so many times, all I ever heard of or used was Dexron II (with no T :) and "Type F"

[@WeberAuto]

Thank you very much!

[@andrewthompsonuk1]

Fantastic information. I hope you set up a transmission museum one day.

[@WeberAuto]

Thank you very much, that would be fun

[@badwrench1618]

Interesting and well presented. Thanks, I learned a few things.

[@WeberAuto]

Thank you very much

[@kevinschmitt4050]

great production on this one!

[@WeberAuto]

Thank you!

[@fredkohlman8860]

Very, very good and really informative!!

[@tl7408]

GREAT JOB ! CONGRATULATIONS AND THANK YOU VERY MUCH !!

[@jorgeborrego3373]

Amazing video. Thanks professor. That will encourage me to try to repair my 1948 Oldsmobile trans.

[@frankcastle797]

Thank you for sharing your knowledge with us sir.

[@WeberAuto]

My pleasure

[@iCutTrees336]

For some reason if I don’t touch my phone and just let KZbin run I end up at this long video every time I think this is KZbins tricky way to let u keep playing ads even if u fall asleep because of this guys voice

[@kswis]

Your student can't possibly understand how lucky they are to have a chance to go through the MASSIVE AMOUNT OF INFORMATION YOU PROVIDE? I think you and I could sit down through a couple pots of coffee discussing these facts

[@robertelee2797]

This is a excellent and informative video! Thank you for your dedicated research. I am old enough to remember cars from the 60s that had non red dyed Trans fluid and when it seems like there was a choice of either dexron or type F.

[@WeberAuto]

Thank you very much!

[@picoboo5048]

Can't wait to watch.

[@WeberAuto]

Thank you!

[@jjunkman599]

Thank you sir for the history lesson. I really enjoyed it. I have subscribed

[@kingnillvwell381]

Thanks, that’s very informative and valuable information .

[@GaryDelgado]

1:27:45 Honda ATF: Dexron was specified for the earliest Hondamatic models, with Dexron II OK as superseding (According to the Chilton Manual for '84-'95 Civic/CRX/Del Sol). Dexron II specified for Model Years (MY) '91 and earlier (Derived from '91 Civic and Accord owner's manuals). Honda Premium Formula ATF spec. for MY '92-2000, with Dexron II OK as temporary substitute (from '92 and 2000 CIvic and Accord owner's manuals). Honda ATF Z1 spec. for MY '01-'10, with DW-1 superseding, and with Dexron III OK as temp. substitute (from '01 and '10 Civic owner's manuals). Honda ATF DW-1 spec. for MY '11-present, except where contradicted, with no substitutes listed except "equivalents" and warning not to mix with other ATF types (from '11 Civic owner's manual). Lastly, There are now transmissions which contradict DW-1 and spec. other ATFs such as Honda ATF Type 2.x and ATF Type 3.x near the fill plug. These are the 9-speed (Type 3.x) and 10-speed (Type 2.x) automatic transmissions. Other vehicles have transitioned to CVTs and the associated fluid. Honda's hybrids appear to still use DW-1 (from '22 CR-V owner's manual). Thank you Prof. Kelly for a great video!

[@christopherpobanz6960]

With a voice like that I wish this guy was a Minister . If I listened to him talk about atf for 1.5 hours just to listen to him.

[@moclepocle]

Thank you for sharing your valuable experience.

[@WeberAuto]

You are welcome

[@ericcorse]

Very interesting sir thank you for this effort.

[@WeberAuto]

Thank you very much

[@ahmednajim3752]

Thanks alot for your hard work to explain to us

[@williamhanna5224]

Very informative video !

[@KrukasT4]

Excellent..Thank you for sharing. From the Netherlands.

[@adrianw3985]

Impressive research you did

[@WeberAuto]

Thank you, it started out small and ballooned into a huge research effort. It was fun though.

[@adrianw3985]

@@WeberAuto looking forward to seeing your next videos in this series

[@buzzofftoxicblog791]

Interesting learned a lot thank you. The original mini automatic gearbox used sump oil!

[@allalphazerobeta8643]

Love the content. Two, things. I'd like to see a video where you heat Transmission Fluid up in a graduated beaker and show us how much it expands. And a video on 90s-00s four speed front wheel drive automatic transmissions. Lots of those cars around for us poor people who like to work on our cars. With Trans problems those cars go for scrape value. The fords were particularly prone to problems. 4CDE was known for being a bit problematic.

[@WeberAuto]

Thanks for your feedback. I will add that to my list

[@TheSleepingonit]

Very impressive history thank you much

[@fotostudio68]

Hello Professor John D. Kelly! Thank you for your video. You give a lot of useful information always. I love your channel! Greetings from Russia. P.S. Beautiful sound is always good and good frame construction!

[@WeberAuto]

Thank you very much

[@fotostudio68]

WeberAuto be healthy! Many thanks for your video!!!

[@marklynch4588]

Great video , I can"t Imagine the time spent on this project ! One thing that would have been of interest is oil sample reports on the different versions of the fluids you had a ready supply of showing the different additive packages . I sure wouldnt want you to open the GM #1 can that was a cool find in it self ! I do remember the Red Lable ATF and Quakerstate Dexron II c cans Might even have a full one at my dads place . I warned some people at wally World the other day to check their manual before dumping any fluid in their car .. sure is confusing now ! Thanks for your work !

[@lcastelano]

Thank you for everything . You are a great man .

[@iivaridark6850]

Hats off! Great work! Thanks!

[@WeberAuto]

Thank you

[@apttabrasil1696]

Good afternoon John. We cannot use DEXRON II or III replacing DEXRON VI, but can we use DEXRON VI instead of DEXRON II or III? Thanks for your kind attention and for your patience. We learn a lot with you. Carlos from Brasil. Have a nice week end

[@DrShock]

Enjoyed the video. I thought you would be interested in the contents of an original Chevrolet Technical Service Bullentin I have dated October 17, 1957 and numbered DR #318. It states "ATF used in 1958 production will be dyed red. This change will enter production at all assembly plants as soon as existing stocks of transmission fluid are exhausted." And goes on to indicate this is being done for leak detection purposes. This TSB provides some evidence this red dye practice began a bit earlier.

[@WeberAuto]

Excellent! Thank you

[@johnsmallwood5082]

Here's one for ya... 3 Allison MD3000 clutch fails in 20k mi. In our 2000 Monaco Diplomat with a Cummins 275. Always transynd, and Allison filters. 4th reman just installed, never left Western Star in Ridgefield WA parking lot, due to #3 solenoid wiring failure (according to diag comp). All engine and driveline components in spec. Allison really wanted it to be someone elses fault. Milage of failures, 1st 70k; 2nd 75k, 3rd 89k. Fluid change 3k ago at Allison authorized shop. No fluid debris, color, smell reported. 2 independent fluid samples report NO contamination, other than very fine clutch particles, under 5 mic. Never gets hot, eng and trans always exactly where they're supposed to be. We are somewhat desperate for the cause of these failures. I've run heavy equipment my whole life, starting in the Army at 17.

[@jimgrazulis3542]

Thank you for the great video. However I must make a comment to correct your statement about the orginal Buick Dynaflow. Under normal driving the shift lever was always left in "D" drive . The torque converter even in the 1st version had enough torque multiplication . After '53 the "Twin Turbine" Dynaflow had even more troque multiplation . "55 the "Flip Pitch" stator also improved performance as did the addition of the 1st Stator between the turbines. I quote the owners manual 'L" . This range is to be used when the "going" is particularily tough such as deep snow sand or long steep hills.

[@WeberAuto]

Great information, thank you.