OD tranny hard to come by?

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I talked about OD with my trans guy just this morning. He says 1990,91,92, A500 is all I should look for.
Parts yard prices have ranged from 350 to 700. The 350 quote is a 4 hour drive away. :( That donor ( 91 van ) shows 188K miles.
Rebuild if needed is 750 which includes reman'd torque converter.
Still atleast half of the GV cost at all done.
 
Technically the GV gives you 6 speeds but for practical purposes it's just an OD that you engage when the tranny is in top gear. No one is going to manually shift an auto by running it through 1st gear then engage the GV, then shift to 2nd and disengage the GV, runn it through second then engage the GV, etc. I am not even sure that makes sense from a gear ratio standpoint. It could be that you shift 1, 2 in the tranny then shift back to 1 and engage the GV, then go to third with the GV off and then to 2nd with the GV on, etc.

I wouldn't bother with the A500 and would look for the A518/46RH. The A500 was used behind v6 engines and the A518 behind v8. I would think it's going to be easier to come across an A518 because very few RAM pick-ups had v6's. The OD unit is the approximately the same size so the floor tunnel surgery will be the same regardless of A500 or A518. Also the A518 would only require a stock type rebuild where as the A500 will need some beefing up which would keep the cost of the A518 rebuild less than the A500.
FWIW, you can use the early than 90 A500's if you cross drill the main shaft in the OD to fix the oiling problems like the 90+ units have. it's pretty straight forward to do and if you pick up a rebuild kit there will be instructions on how to do it.

Also, there are a number of articles on the web on how to rig a couple of pressure switches to the A500/A518 and a switch to the throttle to engage the OD and lock-up automatically.
 
There are some a500 boxes under B150 vans with 318s. The B250 is easier to find but will have the 518. Atleast thats what I'm finding.
I found a entire B250 with recently rebuilt engine and trans, new tires, etc... for 1500 bones. Can I get a loan ? LOL
 
dgc333 said:
Technically the GV gives you 6 speeds but for practical purposes it's just an OD that you engage when the tranny is in top gear. No one is going to manually shift an auto by running it through 1st gear then engage the GV, then shift to 2nd and disengage the GV, runn it through second then engage the GV, etc. I am not even sure that makes sense from a gear ratio standpoint. It could be that you shift 1, 2 in the tranny then shift back to 1 and engage the GV, then go to third with the GV off and then to 2nd with the GV on, etc.

I wouldn't bother with the A500 and would look for the A518/46RH. The A500 was used behind v6 engines and the A518 behind v8. I would think it's going to be easier to come across an A518 because very few RAM pick-ups had v6's. The OD unit is the approximately the same size so the floor tunnel surgery will be the same regardless of A500 or A518. Also the A518 would only require a stock type rebuild where as the A500 will need some beefing up which would keep the cost of the A518 rebuild less than the A500.
FWIW, you can use the early than 90 A500's if you cross drill the main shaft in the OD to fix the oiling problems like the 90+ units have. it's pretty straight forward to do and if you pick up a rebuild kit there will be instructions on how to do it.

Also, there are a number of articles on the web on how to rig a couple of pressure switches to the A500/A518 and a switch to the throttle to engage the OD and lock-up automatically.
Click to expand...



I do..... At the track the RR goes 1st, 2nd, and 2nd over, back to 3rd...makes it's fastest pass that way... Road racing...it can see 1st over, 2nd, to 2nd over..... If i had the 518....it's useless except for 75 mph on the highway...

Now really what trouble is that.... all just a button to push on and off and pull /push the stick....

In my truck many times i may go 1st 2nd, 2nd over, 3rd d, 3rd over, 4th d, 4th over..... it happens so fast it's a not a problem. Much better then a 518....


The GV is extremely helpful at the track... whether it's drag racing, or road racing... road racing with a auto and the gv is great....
Towing with a GV is way better then a od trans, and you can tow in od with the gv even if it's over 14,000 lbs



If you really like the car and intend on keeping it, your best choice, your best overall use and best performance will be with the GV...

the od trans is just a trans with a od after 3rd...
 
MoparMark67 said:
Speaking of gas economy in regards to the over drive... Overdrive will give you about 20-30% increase in fuel economy according to what I have read. I think it's worth it in the long haul. I am looking into installing an A500 into my 67 Dart.

Good luck to you.

Oh and what school are you going to (auto tech school?)
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Im going to Santa Rosa JC haha i wanted to go to an actual tech school like UTI or Wyotech but finances forced me otherwise. SRJC has an awesome auto program though, just no body class
 
I am also interested in an a500 in my Dart. I calculated that with 24.5 inch tires and a 3.91 ratio out back that I would effectively cut the gear ratio down to a 2.50 for highway cruising. Unfortunately for now I can't afford the 2k for a 500 ready to go,....and I would like to see if one would go in an A boy without cutting the tunnel as my car is unmolested and would pretty much like to keep it that way.
 
An A500 or an A518 is pretty much the same from the main case back (i.e. The OD section). With either you need to do floor surgery.

FWIW, I have an A833OD in my Barracuda. With 3.55 gears and 27" tall tires I am turning just over 2000 rpm at 65 mph and getting 22mpg with a 370HP 360.
 
dustoff440 said:
I am also interested in an a500 in my Dart. I calculated that with 24.5 inch tires and a 3.91 ratio out back that I would effectively cut the gear ratio down to a 2.50 for highway cruising. Unfortunately for now I can't afford the 2k for a 500 ready to go,....and I would like to see if one would go in an A boy without cutting the tunnel as my car is unmolested and would pretty much like to keep it that way.
Click to expand...

I don't see how there's any possible way it'd fit cause like DGC said the O.D. section of the A500 is the same as the one on a A518. The main case on the A500 might be an inch shorter than an A518 but that's about it. That's not enough to make the difference needed to fit that O.D. unit in. Only way to keep from doing surgery is to use a Gear Vendors o.d.
 
Spoke to GV a while back, only thing it takes to fit is a couple of small dimples. Had a picture of one installed in an a-body, I will look for it.....can't find it....
 
dustoff440 said:
I am also interested in an a500 in my Dart. I calculated that with 24.5 inch tires and a 3.91 ratio out back that I would effectively cut the gear ratio down to a 2.50 for highway cruising. Unfortunately for now I can't afford the 2k for a 500 ready to go,....and I would like to see if one would go in an A boy without cutting the tunnel as my car is unmolested and would pretty much like to keep it that way.
Click to expand...

I can understand that. My thinking is if I'm putting subframe connecters under my car anyway I may as well do the trans tunnel and trans support mod at the same time. Tie it all together with more clearance for dual exhaust in that area too.
 
dgc333 said:
An A500 or an A518 is pretty much the same from the main case back (i.e. The OD section). With either you need to do floor surgery.

FWIW, I have an A833OD in my Barracuda. With 3.55 gears and 27" tall tires I am turning just over 2000 rpm at 65 mph and getting 22mpg with a 370HP 360.
Click to expand...

You're not having any carbon issues running that low of RPM's with that much Horse power?

-Mark
 
73charger said:
Im going to Santa Rosa JC haha i wanted to go to an actual tech school like UTI or Wyotech but finances forced me otherwise. SRJC has an awesome auto program though, just no body class
Click to expand...

That's awesome man! I am currently at Wyotech. So far it's pretty cool. Good luck to you in your auto program.

-Mark
 
73charger said:
just curious. i have an a904 but i want to have an a500 or a518 OD tranny instead. what cars would i look at in the local pick n pull for these trannys?
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I'm on the same warpath (a500), did you get an answer on which models and year to pick over at the pic - n - pull?
 
MoparMark67 said:
You're not having any carbon issues running that low of RPM's with that much Horse power?

-Mark
Click to expand...

Most of my driving is in the 1500 - 2000 rpm range and have not had any carbon issues. No reason to have any carbon build up if the carb is tuned properly.
 
Check the Grand Cherokee 92-94/95ish for the 46rh. The ones that came with the 318/5.2. I know there should be some in the boneyards... I remember working at the dealership on the 1998 Grand Cherokee with the 5.9 with awd. That thing was a beast!!!:snakeman: The ones round 96 97 went to the electronic one.
 
dgc333 said:
FWIW, you can use the early than 90 A500's if you cross drill the main shaft in the OD to fix the oiling problems like the 90+ units have. it's pretty straight forward to do and if you pick up a rebuild kit there will be instructions on how to do it.
Click to expand...
Anyone else know anything about this information ? Did the early 88,89, 90 A500 have a oiling problem in the overdrive section ?
 
>If you run it with an A-998/999 with the low gear set, you get;
2.74-2.14-1.54-1.20-1.00-.78 GV ratios in red,splits of .78-.72-.78-.83-.78od. You get to short shift first and you get a short 5th. A pretty nice 6-speed.
>If you ran it with an A904, you'd get
2.45-1.91-1.45-1.13-1.00-.78od; GV in red, splits of .78-.76-.78-.88-.78.
You get a tighter 1-2, and a really tight 4-5 which you would probably never use, instead shifting straight from 2-over to 3-over, giving you the equivalent of a close ratio 4speed auto with a .69od. Works well with 3.73s to 3.91s. I would run this with one camsize smaller than with no splitting.

But like somebody said, if you gear it right,you will only be using two gears anyway to 60 mph so it really isn't all that helpful. However on the WOT run blasting thru the gears with just 1200 or 1300 rpm drops is extremely addictive.
But the best part is running 3.91s to 4.30s, cuz the engine spools up really really fast.
To be sure the GV does have a couple of idiosyncrasies that have to be addressed before you go nuts on it.
It fits in the tunnel no problem, like they say, just a couple of dimples.
I run my GV as a splitter quite often.( manual trans). A lot actually. My street combo worked great with a 223/110 cam.

However, If I was go automatic, I would go A518/A500Loc-up, and here's why;
This trans actually works like a 5.5 speed.
You get the 4 regular hard-ratios, plus the stall is a little higher, and the TC has an internal TM (Torque Multiplier) that can be as high as ~2/1 @ zero mph, and diminishing to ~5% as the car moves out.. And the loc-up is worth about a quarter to a half gear.
>So the math I get with the A518 is ;
2.45-1.45-1.00-.69od in the main box. Lets put 3.91s in the back and get road gears of ;
9.59-5.67-3.91-2.70. Now lets factor in 5% in the TC, and I get
10.07-5.95-4.11-2.84.. and finally lets factor in the instantaneous starter gear of 2/1 and take the 5% out in loc-up; I get;
(19.2 >diminishing to) 10.07-5.95-4.11-2.84od-2.70locked up.65=2180 with 27s. I call it 5.5 gears, lol, and worth every penny of the install.

With the A500(2.74-1.54-1.00-.69), 5% slip,and 3.73s, I get
(21.46>)10.73-6.03-3.92-2.70-2.57locked up, 65=2075 with 27s. Check it out; that's 105rpm less on the hiway, with tad more TM in both first and second, and very similar the rest of the way.

Happy HotRodding
 
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AJ/FormS said:
I run my GV as a splitter quite often.( manual trans). A lot actually.
If you run it with an A-998/999 with the low gear set, you get;
2.74-2.14-1.54-1.20-1.00-.78 GV ratios in red, splits of .78-.72-.78-.83-.78od. You get to short shift first and you get a short 5th.
If you ran it with 3.91s or 4.10s it would be killer on the street, yet, calm on the hiway.
But like somebody said, if you gear it right,you will only be using two gears anyway to 60 mph so it really isn't all that helpful. However on the WOT run blasting thru the gears with just 1200 or 1300 rpm drops is extremely addictive.
But the best part is running 3.91s to 4.30s, cuz the engine spools up really really fast.
To be sure the GV does have a couple of idiosyncrasies that have to be addressed before you go nuts on it.
It fits in the tunnel no problem, like they say, just a couple of dimples.
Click to expand...
Thanks for this reply..But I don't see how it tells me anything about cross drilling the mainshaft of the A500 for an oiling problem ???
 
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