Author Topic: i need a new tranny guy. 518od pressures  (Read 1653 times)

Offline leanburn

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i need a new tranny guy. 518od pressures
« on: July 16, 2013 - 11:12:23 PM »
 the guy that has been into my 518 twice now still is baffled. my overdrive will not engage, he THINKS it has something to do with the shift kit used won't allow the overdrive to engage, and that the pressures need to be tweaked. this thing is also a slushbox, he says that's the way they are. one thing ive learned is if u wan't it done right u gotta do it yourself, even though i'm clueless when it come to tranny's.
 is this something i can do with basic tools? anyone have any pointers and where/how to start?




Offline nqkjw

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Re: i need a new tranny guy. 518od pressures
« Reply #1 on: July 17, 2013 - 05:43:41 AM »
Sorry I don't know a lot specifically on them as I had a high performance shop rebuild mine but I did learn a bit about it along the way.
Firstly they don't have to be a slush box.Mine is anything but.
Mine has a shift kit and some pretty stiff pressures as I also had a custom lockup convertor built for heavy duty towing which requires big pressures.(that's why mine failed.the lockup clutch wasn't engaging under heavy load and put cast iron dust all through the tranny.
When you say OD isn't engaging is it the OD or lockup clutch?
Mine's in a 2000 4x4 1500 Ram with blown 360 magnum.It has an "overdrive off" button.Possible this isn't hooked up or not working?
The lockup clutch is operated by a solenoid inside and is well known as a commonly failing part.Recommended they be changed any chance you get.
Sorry I can't be of more help but at least it's a start.
Burnouts are cool but Traction is the Action

Offline leanburn

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Re: i need a new tranny guy. 518od pressures
« Reply #2 on: July 17, 2013 - 07:48:25 AM »
I don't have the lockup style converter so I'm gonna say its the overdrive. I'm definitely getting 12v to tranny but as far as selonoid goes I will have to find out how to check, thanks
 When you manually shift to first will it stay in first at any rpm ? Mine shifts at about 20mph even with shifter in first, this is under light acceleration.

Offline nqkjw

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Re: i need a new tranny guy. 518od pressures
« Reply #3 on: July 17, 2013 - 08:14:14 AM »
It shouldn't shift out of 1st if you're holding it in 1st.
Could be a clue as to what's wrong.
Burnouts are cool but Traction is the Action

Offline Haddixj

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Re: i need a new tranny guy. 518od pressures
« Reply #4 on: July 17, 2013 - 10:05:19 AM »
Where are you located? I would go to the local racetrack and find who is building trans for the bracket racers. I have a friend of the family who builds mine.  Also you can look for who does diesel trans as the early trucks used a 518

Offline jimynick

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Re: i need a new tranny guy. 518od pressures
« Reply #5 on: July 17, 2013 - 11:28:23 PM »
One of the members here, I believe it's Transtacman, is a transmission tech and if you could get his attention, he'd be the guy I would ask your questions to. He's a nice guy and he's forgotten more about autos than I'll ever know. Just my  :2cents:

Offline leanburn

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Re: i need a new tranny guy. 518od pressures
« Reply #6 on: July 18, 2013 - 12:07:03 AM »
One of the members here, I believe it's Transtacman, is a transmission tech and if you could get his attention, he'd be the guy I would ask your questions to. He's a nice guy and he's forgotten more about autos than I'll ever know. Just my  :2cents:
[/quote

Yeah, I'm hopeing he chimes in

Offline leanburn

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Re: i need a new tranny guy. 518od pressures
« Reply #7 on: July 20, 2013 - 09:04:29 PM »
 ive been doing some googleing last few days, ive been reading that the governor has alot to do with the shift characteristics. i know my tranny has a diesel od, gas valvebody and gas governor. does anyone know if this is the right combo or should i have the diesel governor?

Offline ShelbyDogg

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Re: i need a new tranny guy. 518od pressures
« Reply #8 on: July 22, 2013 - 11:18:45 PM »
The 518 OD non-lockup converter has a 2 pin connector on the side next to the shift shaft. you supply 12 volts to one pin and ground the other to put it in OD.

The 518 OD lockup converter has a 3 pin connector on the side and the center pin gets 12v. When the other 2 pins get grounded, one puts it in OD, the other locks up the converter.

Are you getting 12v to the pins?  Just use a switch for now to see if it kicks in.
Rob

3 E-bodies, Megasquirt-1v3.0, Edelbrock Pro-Flo-1, Holley C950, FAST EZ-EFI; say no to carbs...yes to throttle bodies

My Pace Car restoration thread:
http://www.cuda-challenger.com/cc/index.php?topic=44869.0


Offline leanburn

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Re: i need a new tranny guy. 518od pressures
« Reply #9 on: July 23, 2013 - 12:47:24 AM »
I definitely have 12v to connector, it is a 2 pin.

Offline tactransman

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Re: i need a new tranny guy. 518od pressures
« Reply #10 on: July 24, 2013 - 07:40:51 PM »
It sounds like your shifter is not really going all the way to manual low if it shifts out at 20 MPH when you still have it in low. Diesel/ gas governor difference will NOT stop you from having OD. It sounds like this guy doesn't know what he is doing. It sounds like the shift kit/VB was not done right. "this thing is also a slushbox"  Throttle pressure sounds too weak also.
Terry-tactransman 
Torqueflite/Automatic Transmission Specialist
Union, Mo.
Give a man a fish and he eats for a day,teach him to fish and he eats for a lifetime.

Offline leanburn

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Re: i need a new tranny guy. 518od pressures
« Reply #11 on: July 28, 2013 - 02:00:23 PM »
yup.he took one more crack at it, changed valvebody and it works awesome now.

Offline tactransman

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Re: i need a new tranny guy. 518od pressures
« Reply #12 on: July 28, 2013 - 02:31:37 PM »
Good deal.
Terry-tactransman 
Torqueflite/Automatic Transmission Specialist
Union, Mo.
Give a man a fish and he eats for a day,teach him to fish and he eats for a lifetime.