A833 Lubricant

[wedg2go]

I remember when I use to own a 1977 D100 with a four speed A833OD. I can still picture the owner's manual instructing to use ATF. At the time I thought it was odd, but after some trial and error I concluded ATF was the correct lubricant to use in that particular transmission.

Skip forward 42 years and so many different brands with different viscosity ratings, that it boggles the mind. The previous owner, of my ride, informed me he used a synthetic lubricant. Didn't tell me which brand or viscosity. Just that it was synthetic.

After researching, I am questioning the use of ATF or to go long and install an actual synthetic GL4 gear oil. It has leaked down considerably, with the reverse detent leakage, that I thought now would be a good time to swap it out. The question is which brand and which viscosity since it rarely hits 90 degrees (F) here?

Thoughts?

 

[toolmanmike]

I use Pennzoil Syncromesh.

 

[dolphin3111]

Polyalphaolefin (PAO) synthetic oils (almost all automotive synthetics) are are compatable with standard mineral oils.

Dexron ATF was supplied with the A833 and A833OD transmissions on new cars since the early 1970's. Transmissions with ATF tend to be a little noisy at idle in neutral. But some folks find that gear oil like 70W90 makes the transmission shift hard and consequently miss the 1-2 shift occasionally. Some people mix ATF and 70W90. Both Dexron ATF and GL4 gear oil (synthetic or mineral), or mixtures would be acceptable.

All that being said, PAO full synthetic oils, are superior luibricants because they have a tendency to bond to metals on a microscopic level.

 

[rklein71]

I tried gear oil in my four speed up in Idaho...in the winter, the car would lurch forward in neutral because the oil was so thick.

 

[moparlee]

Brewer's Performance recommends SAE 85W-90, GL4.

 

[Daves69]

If ya' live up in the tundra region you may actually need ATF!

 

[Rob C]

Mobil one synth oil here.

 

[wedg2go]

Thanks everyone for your suggestions. I am still at odds over gear oil vs. ATF. Unfortunately, I live in a region where temps can drop below 0 and go as high as 95. Not that I would go cruisin' when it's below freezing, but this selection process of what to use can be both confusing and intimidating with the extreme temps that go on here. So, it becomes concerning when you need to do the right thing for your machine.

I am thinking of going the "Trial and Error" route (sometimes not the best idea). Meaning, to see if a good 75w-90 syn will work (I hate the rattle - Even with my sad hearing I can still hear it). If not, then look into the Penns or Mobile. If not that, then ATF and let er rattle.

Sidenote: If it sounds like I am still confused, it's only because I am.

To add to the confusion with a...

BTW - The previous owner/builder told me he used syn. What brand, I don't know? I can say it's not as thin as ATF and yet not as thick as syn gear oil and it's "purple" in color (not red) (I don't believe it's "Royal Purple" - I don't know for sure?). This, what ever it was, worked great. Unfortunately, he didn't list it in work sheets and I can't contact him since I lost the number.

 

[Steve340]

I did quite a bit of research on the internet about what type of oil to put in an A833.
The guy that made the most sense recommended GL4 because it was compatible with the type of material the synchromesh rings are made of.
Why not email Brewers I have found them very helpful.
Go with the oil Moparlee has recommended in his post.
My 2 cents - put synthetic GL4 in it and see how it is. A mineral oil can go gloopy in low temps but the synthetic should not.

 

[volunteer]

As far back as I remember, my '69 Coronet (Super Bee) glove box book stated that the factory fill was indeed ATF - - but it then stated that if 'gear-rattle' at low/idle speeds becomes objectionable - drain and refill with 80w-90 (mineral). Likely no synthetics back then. From experiences with a multitude of trannys and transaxles over the past 50 years, I concluded the determining factor for the perfect (most suitable) viscosity grade comes down to the condition of the trans, the size of the syncros and the 'ambient' temp where most of the shifting will be done. In other words, start out light and go heavier. Many units came from factories with a wide array of viscosities - with several using 10-30 or 10-40 engine oil. If you go synthetic, better to choose a lower viscosity as a 75w-90 could prove too heavy AND 'slippery' to allow syncros to 'grab'. Result is a pesky (mostly) 1 - 2 'gritch'. Same result with a heavy oil in cool climes. Yes, fine once tranny warmed but, never a good idea to allow syncro teeth to make noise.
My RX7 came with 80w-90 but I tried everything from ATF on up. Best of all has been 15w-40 (diesel quality) engine oil but I am now using straight 50 weight (Petro-Can) synthetic. Slightly stiff (1-2) when ambient below about 60F. but no matter to me as car parked until next April or so.

Oh, and one more suggestion would be to replace (whatever) fluid more often than suggested in any owners' manual. ie: at least once every two years - or no more than 10K. miles. It's cheap insurance.

 

[flohemi]

Hello, back in the late 80' s we techs at the dealership we changing the gear oil out to ATF for hard shifting in cold weather, I think it was a bulletin from Chrysler, I think you are over thinking it, I'm in New England and it gets cold here, sounds like you are also. I would put a good quality ATF back in it .

 

[i_taz]

I'm leery of synthetics in vintage equipment that didn't have the metallurgy designed for it....puke out a pinion bearing on a Dodge van I put Mobil 1 in...