Spitballin' here. Should have paid more attention when others asked basically the same question. And of course, I don't seem to be able to use the right search words.

What trans uses a simple on-off button for the OD and no electronics? A500 or 518? And would it live behind a 360 in a pick-up doing moderate towing?

Thanks,


Tim

I'd say look for an early (1988-1995) hydraulically controlled A-518. You can wire the OD to engage with a switch or even engage automatically using pressure switches. Be aware that the non lockup units (1988-1992) are much easier to wire through a switch. You just need 1 switch to engage the OD unit. The later units (1992-1996) with the lock up converters would need 2 switches (one for OD, the other for the converter). That would be cumbersome to control with switches alone, so you really would need pressure switches and/or a timer for the lock up converter.

Thanks, the '88-'95 unit is the one I was thinking of. Do you have to activate the OD very time or can you simply leave the switch in the "ON" postion?


Tim

If you leave it on the transmission will shift immediately into fourth gear as soon as it shifts into third. It will still down shift on its own with speed, but will not down shift with the kick down. Leaving it on effectively makes it a three speed with a non-functioning kick down. I don't think it does anything bad to the transmission itself. This is only for OD though. You cannot leave lock-up on if you have a model that does have it - that will do damage.

Honestly though, a pressure switch and vacuum switch is all that you need to automate fourth gear. Add one more pressure for lock-up. It's not complicated at all.

Thanks. Food for thought. Just thinking of a possible future project and how to do it.


Tim

Everything you need plus instructions for it to work without driver input. Once it;s installed is handles the chore for you. $88 plus they are current running a 10% off deal.

https://transmissioncenter.net/shop...ere-for-727-to-46rh-swap-wiring-diagram/

Thanks, Sniper.



Tim

sniper is right. i have a friend that has a 5.2 and 518 in 37 chrysler. he put one of those kits on and simply loves it. so much so, that he ordered on for his 49 olymouth. now i am ordering one for my 85 d150 that i am putting a 5.9/518 combo in.

CRT John Cope can fix you up

RB, what did your friend select for the "speeds" for the OD and lockup? I am thinking of going with "44" for OD and"50" for lockup. Mine will be a 42RH behind a built up 318, want to use 3.55 gears in an ebody.

he went with 44 and 50 that patc lets you choose when picking speeds. but he also ordered an adjustable one for 49 for extra monies.

I'm actively looking into the 4l65 swap for my Gen3 Cuda because it's a small case design with OD and lockup. I don't know enough about it quite honestly to "sell" the idea to anyone else but it may be something to look into for you.

Because it's a GM trans, parts seem to be available, affordable, and you can buy supporting parts and pieces at Jegs/Summit

I put a 2002 A500 in my Charger behind a 1995 5.9 Magnum. I mounted two switches on the console. With 3.55 gears I did not need to switch them on until I hit the highway. It never bothered me

I can see this having upsides if the OP was inquiring about an OD automatic behind a big block, but seeing as how Mopar made transmissions that bolt right up to his small block it probably isn't worth it. When I stuck a 518 in my Fifth Ave behind a 360 I did it for under $1k. The aftermarket support isn't lacking either.

Then again, if it doesn't require surgery to make it fit then toss everything I said right out the window.

Kind of defeats the purpose of having an automatic, doesn't it?

I have an a500 behind the turbocharged 383 in my 70 Fury. Psi switches for OD @ 45pmh and lockup @60mph, 3.91's and 28" tires, I don't like to lug it around. In the C body no tunnel work, just a custom mount.

Thanks for all the input. I just scored a Dakota QC 2wd, 5 spd. with no engine for a song. Durango is a little ragged after the 2 not-my-fault accidents & really miss having a truck. Engine & many of the parts from the Durango will live on in the Dakota. I think it will be a fun little ride. Reason I asked about a simple OD auto swap is if I get tired of rowing a stick. I'm not getting any younger & since we moved back closer to Atlanta traffic is a bear.

Thanks again.



Tim

Since the A 500 is based on the later 904, it should have the 2.75 low first gear. That would help staring when pulling a load.

A 500 or a 518 will directly swap with each other without driveshaft swaps, etc. Same exact OD housing used on either one. Unlike a swap between a 904 and 727, these OD transmissions are the same overall length. I've put 518 (46RH) in place of 500 (42/44RH) a couple of times now. I'd go with the heavier duty trans of them every time.
But then I live 2 county's south of Chicago, among corrnfields, avoid Chicago like the plague anyway, and with all else being equal I'd rather row gears any time I can. Though I've been hurt badly twice over the years (right knee and then the ankle several years later) and both times the DR saying whether I could drive depended on whether my ride was auto or stick... Both times I had stick equipped vehicles so had to borrow vehicles or be chauffered around.
But yeah I have heard that Atlanta is 10x worse to drive around in than Chicago which is plenty bad in its own right. I'll have to take the word on the street about Atlanta, never been there.

I've been to Atlanta during rush hour many times. Let's just say I would rather slam my male member in a sliding glass door than drive through that everyday.