What can you tell me about the 999 Transmission?

[Khyron]

Was speaking to a knowledgeable gentleman today about my possible 727 Trannie upgrade, He suggested that the e999 has a better first "2.54 ratio" and second "1.54 ratio" gear and I would benefit better with the 999 Trannie then the 727, and I would also save weight.

So who knows about these mysterious transmissions?

How to I identify one since it is in a 904 case?
What years were they made?
What stampings are on them?
What vehicles are they in?

[Plumcrazy]

They were more common in the trucks and B-vans but were available in cars also.
They were also called 904 heavy duty's
First gear was 2.74 to 1  instead of 2.47 to 1
Second gear was 1.54 to 1  instead of 1.45 to 1
Both are lower than the standard gear ratios.  In a small block B-body they really make a noticable differance.  Just adjust the throttle linkage to raise the shift points a little higher.
I also think the front clutch has an additional clutch disc.  In newer Chrysler nomenclature the 904 wouild be called a 30rh.  The heavy duty 904 would be a 32rh.
The second digit identifies the load capacity of the transmission. I think 727's are a 6 for comparison.
You can install  the lower gear ratios in a 904 that doesn't have them fairly cheaply.

[Khyron]

so what would I tell a salvage yard to look for to get my hands on one? any specific cars or years to look for?

['CUDA360]

No 904s were ever made for big blocks

904s are a great choice and my friends and I have raced them for years with very few failures.

If you have a small block then use the 904 but get the low gearset for it (2.74). The low gear just lowers the first and second gear but leaves the third gear stock sort of like a poor mans overdrive with a kick.
(better then going to a 3:90 rear)   Those low gears were found in Police cars and small motorhomes, your tranny guy should be able to get you one for under $100.00.

A quality valve body is a must for 904s. I recommend Turbo Action's Cheatah (reverse pattern)

To tell the difference between the 727 and the 904 just measure the length between the front of the case to the tail.

34.39" for 727 not including 4 wheel drive truck trannys
30.50" for 904

/six engines got the A-904, 318s got the A-998 and 360s got the A-999

My Hot Rod 904/A-999 with the tranny brake in it sez 036-1 in big letters on the case.   I don't know if they all do

When they fail they fail big...   usually when the rearend gear breaks you zing the RPMs on the engine and the sprag in the back of the tranny stops real quick breaking the inside of the case.

Don't use a cheapo valve body and don't neutral drop them
I had one that lived over 900 quarter mile runs and a buddy of mine had one that went over 1200 runs

When they break just take out the valve body and the low gear and build a new one. Ther're super common and not worth fixing

[Khyron]

Awesome information!

My Charger does have a 360 small block in it So I think this may be the way to go. So your saying find one of this A-999, it will be behind a 360. Get a new valve body from Turbo Action, <reverse needed?>.

I have a 727 small block trannie, and know it's longer then the 902, but having those dimensions are good. Thanks

Possibly has a 036-1 on the case, I'll check into that

['CUDA360]

I'm not saying you have to have the Cheatah valve for it to work.  I'm just saying it works real well and seems to help keep it together.  (my opinion)

Good luck

[John_Kunkel]

The A999 looks no different externally than the A904, the part number stamped in the passenger side pan rail can be used to identify the type.

Not all A999's have the low gearset, the A999 was introduced in '74 but the low gears didn't arrive until '80. In addition to the extra front clutch disc, the A999 has a wider kickdown band.

If one decides to use the smaller transmission, the A999 is the one to get but it will never match the 727 for durability.

[Khyron]

thanks, do you happen to know the part numbers that would show it as a A999? non lockup?

The 727 case is about 2 - 3 inches longer then the 904's. That’s why I was thinking about the A-999, same dimensions as the 904 and better gears in first and second. I would be able to use the present drive shaft.

I'm about to get a 440 in a week or so. I would like to start putting some money into it. So putting top dollar into a 727 small block trannie makes no since because I can't reuse it. Yeah I could most likely sell it, but I don't think I would get my money back, we all hate loosing money.

The whole idea was an A-999, shift kit, bolt it in for a year while I build the 440 and its transmission.

I agree 100% percent what everyone is saying, and If I was keeping the small block. I would build the 727 in a heartbeat. That’s why I got it 

But for a year I was thinking of a A-999.

Then when done, sell the massaged 360 and trans, and put the money were it belongs. In a Big Block

[John_Kunkel]

This link is to a page with part numbers up to '86, the A999 is also sometimes listed as a HD A904:

http://www.mymopar.com/downloads/transguide.pdf

[Khyron]

thanks I modifyed my responce with more of a reason i'm interested in the A-999 instead of the 727 thanks for the help