This is probably not a perfect explanation but I hope I’m close enough... It depends on how the transmission was designed.

Different metals, different bearings, different clearances, different gears, different synchronizers - all require different types of oil. You can’t dump anything you want in there unless you know it will flow fast enough through the smallest oiling hole in the transmission.

Synchronizers work by creating friction and are made from different materials. One material may not generate enough friction with the wrong oil and cause gear grinding while others may generate too much friction and wear the synchros out prematurely.

That's not to say yours won’t work fine with wheel bearing grease mixed with bull butter. I don’t know. I also don’t know what the factory recommends for an A833OD - maybe it’s 90 weight? I use what the factory recommends until I hear something different that I can trust.

Danny

I poured in some Mobil1 synthetic. I have yet to drive it. Some guys on Moparts said to use Castrol synthetic. I didn't see it on the shelf and bought the Mobil.


I used to drive 18 wheelers. I have a '79 Maxivan. When I bought it a piece was missing from the grille. I put a R/T emblem in there with a black back ground. People asked why it was an R/T? I told them it was a special edititon...........

I have been installing carpet and floor covering since '93.

It's a RUG TRUCK!!

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'72 Duster 198 stock cam, 3:23's Hookers on jack stands for 8 years in the driveway
'79 Maxivan 360 Offy Qjet Comp RV cam/rusting in the driveway.
93 D350 160HP Cummins Auto Dually Clubcab needs a injector pump
2005 Golden Couch Buick

I am first alternate at the Nashville campus for CDL training. I might be going to CDL school in another month get back driving for a living. It's been since '87.

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'72 Duster 198 stock cam, 3:23's Hookers on jack stands for 8 years in the driveway
'79 Maxivan 360 Offy Qjet Comp RV cam/rusting in the driveway.
93 D350 160HP Cummins Auto Dually Clubcab needs a injector pump
2005 Golden Couch Buick

And judging from what I've found on the internet Chrysler couldn't make up its mind in different manuals and statements which kind to use. I can't find anything actually official on it, but I've found "quotes" ranging from ATF A to 150 SAE gear oil. (Always believe what you find on the net, right?)

People who actually tried different things actually seemed to gravitate back to 80 or 90 gear oil.

Thanks

RK

My last A833 really liked Redline MT-90. Standard GL5 hypoid oil is too slippery for the syncros to work well. If you use conventional lube I'd use a 75W-90 or 80W-90 GL4. The A833 I just went through will get Redline when it's in the car.

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Joshua

I tried 75/90 in my 833 before it's rebuild and it did not like it,after rebuild tried some syn 75/90 and it liked that even less.Regular ole auto trans fluid in her now and she's happy,me too

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83 B-150 slant 6,4 speed. 79 B-300 360 pathfinder 4x4. 74 W-300 318 4x4 git-r-done 80 B-100 sl6,4speed

I'd bet $1 both the gear oils you tried were GL5.

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Joshua

GL5??

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'72 Duster 198 stock cam, 3:23's Hookers on jack stands for 8 years in the driveway
'79 Maxivan 360 Offy Qjet Comp RV cam/rusting in the driveway.
93 D350 160HP Cummins Auto Dually Clubcab needs a injector pump
2005 Golden Couch Buick

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Joshua

Interesting. "Exceeds GL5" seems to be pretty common in parts houses.

RK

Does anybody know the amount of displacement of axes in A833's?

RK

I think it all depends on the synchro's that are in the tranny. The OD tranny's definitley did not use 75/90. And the trans from the 60's, as far as I can remember used the 75/90. Not sure what they used in the OD's but it was either ATF or motor oil. I think it depends on a number of things as far as what has been done inside the box. Synchro rings with oil holes and various other things. I'd call Passon or Brewer's. The synchros work on friction so it can change the requirments of the lube depending on the type of synchros used.

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1979 W150 Shortbox
225, NP435, 9 1/4, Dana 44

The Good Life.

Transmissions that use gear oil (not ATF) either are speced GL4 or GL4/GL5....

So unless they specifically say GL5, you can't use it........

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

Quote from 1977 FSM:
"All three and four speed manual transmissions are filled with Automatic Transmission Fluid at the factory. If it becomes necessary to add fluid to either transmission, Automatic Transmission Fluid of the type labeled Dexron Automatic Transmission should be used.
If objectionable gear rattle at idle speed or during direct gear acceleration is apparent, the factory fill fluid may be drained and the transmission filled with Multipurpose Gear Lubricant GL-4 or 5. Viscosity grades conforming to SAE 75W. 75W-80, 85W-90, or 90 are recommended"

The same manual lists the 4 speed manual transmission as "Overdrive-4"

My 1965 FSM has recommendations all the way up to 140 Weight for the 4 speed of that period.

I used Valvoline 75W-90 synthetic with GL-5 rating in my recently installed 833 OD in my 65 Dart. I msy shift to automatic fluid in the winter if shifting gets tough below freezing temps.

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1965 Dart 125k, 225, Carter BBD Super Six, 2 1/4 single exhaust., sbp manual scare-bird front disc, 7 1/4 rear 2.94 sure grip, 15 x 4.5 wheels, 833 OD with hyd. throw-out bearing, electric fan, ram air/heated air, Accusump.

The lube comments in this thread remind me of the first time my Challenger was serviced. The Shell station across the street from the parts store I drove for at the time (1970s) drained the trans (a 4 speed) and replaced the ATF with 90W gear lube. I was back in less than 15 minutes, it was not even possible to shift the trans with 90W in the box.

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66 Valiant, 225.
84 Van, 225.
71 Maxi-Van, 318
60 Valiant wagon, 225
87 Maxi-Van, 318 4spd