Notices
1999 - 2003 7.3L Power Stroke Diesel  
Sponsored by:
Sponsored by: DP Tuner

mechanical diode in trans?

Thread Tools
 
Search this Thread
 
Old Feb 3, 2008 | 12:51 AM
  #1  
hrhankypoo's Avatar
hrhankypoo
Thread Starter
|
Freshman User
Joined: Jul 2007
Posts: 37
Likes: 0
From: Buffalo
mechanical diode in trans?

I have seen a few threads on here talking about a mech. diode in the trans. of the 01. I was wondering what is this and why is it bad. My truck had a rebuilt trans in it when i bought it and wondering if you could tell if it still had this. You wouldn't think they would put something bad back in the truck.
 
Reply
Old Feb 3, 2008 | 01:00 AM
  #2  
Tenn01PSD350's Avatar
Tenn01PSD350
Post Fiend
Joined: Feb 2006
Posts: 11,892
Likes: 2
From: Middle Tennessee
Have a look here at the TSB. If you need help with the dataplate for build date let me know. First is year, second is month via letter, and third is date of month. If it was rebuilt you have no way of knowing if the intermediate assembly was replaced. The retro conversion or diode fix costs about $250 just for the parts. So if the diode was not failing, it may not have been replaced.
 
Reply
Old Feb 3, 2008 | 01:17 AM
  #3  
hrhankypoo's Avatar
hrhankypoo
Thread Starter
|
Freshman User
Joined: Jul 2007
Posts: 37
Likes: 0
From: Buffalo
Do these go out at random or do they normally last a certain amount of miles? My trucks build date is 01/01 so it did have one from the factory. I am guessing that they replaced it because I haven't had any troubles for the 30,000 or so miles that I have had the truck.
 
Reply
Old Feb 3, 2008 | 01:56 AM
  #4  
Tenn01PSD350's Avatar
Tenn01PSD350
Post Fiend
Joined: Feb 2006
Posts: 11,892
Likes: 2
From: Middle Tennessee
Mine is still in there at about 63k. It either works or it doesn't, you will know immediately.
 
Reply
Old Feb 3, 2008 | 01:59 AM
  #5  
Clint40's Avatar
Clint40
Senior User
Joined: Feb 2005
Posts: 416
Likes: 0
From: Mid Michigan
They do go out in random but usually within 100,000 or near there. The diode is a three part device ( I believe ) that somehow allows the trans to shift up or down. It looks like a ring that slips into another ring then into a housing ring so to speak. I,m no trans mechanic but just went through this last week. The inner ring has a slight shoulder on it and mine was missing half of this shoulder and took out a few other items BUT I didnt drive it much once I realized what my trans was doing so major damage was slight. I needed a new assembly set (77.00 ) a filter,set of pump gears (26.00 ), drum conversion diode kit (219.00 ) then I desided to do the torque converter ( 325.00 ) and a tugger kit (127.00 ) which I am VERY PLEASED with. Whole job was 1450.00 with fluid, labor, parts . My trans has never shifted so good, I mean its unreal compared to stock, it is SMOOTH, solid and I was told should pull a house if needed. ALSO I am going to instally myself a additional trans cooler to eliminate heat better which is recommended in the 01 such as mine.
 
Reply
Old Feb 3, 2008 | 02:24 AM
  #6  
62trvler's Avatar
62trvler
Senior User
Joined: Mar 2006
Posts: 204
Likes: 0
From: Michigan
Clint40, Did you have a dealer perform the work or some independant? That far along and I might be thinking of a BTS tranny. I need to find my build date first.
 
Reply
Old Feb 3, 2008 | 03:06 AM
  #7  
AustinS's Avatar
AustinS
Laughing Gas
20 Year Member
Joined: Jul 2003
Posts: 1,157
Likes: 1
From: Littleton, Colorado
Clint40, you should also think about installing a transmision filter on the return line from the cooler just in case there's a few shrapnel pieces that didn't get flushed out. It would definitely be a buzz kill if something happened to the new one. The one Ford recommends with every rebuild is just a Magnafine. For $15-$20 it's cheap insurance.

Austin
 
Reply
Old Feb 3, 2008 | 05:32 AM
  #8  
AustinS's Avatar
AustinS
Laughing Gas
20 Year Member
Joined: Jul 2003
Posts: 1,157
Likes: 1
From: Littleton, Colorado
hrhankypoo,

They rebuilt plenty of them with the same parts lousy parts in the early days. That was before they figured out ( decided to do something ) intermediate-one way clutch, brake drum and clutch plates and the associated parts.

If your transmission was rebuilt in the last 2-3 yrs, you're more than likely okay. If you start getting funky shifting especially involving second gear or low gear when you mash on it, you might want to investigate it further.

Other than that, keep up on the maintenance and enjoy it.

Austin
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

 Joe Kucinski
story-1

2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

 Brett Foote
story-2

Top 10 Ford Truck Tragedies

 Joe Kucinski
story-3

AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

 Brett Foote
story-4

Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

 Michael S. Palmer
story-5

Ford's 2001 Explorer Sportsman Concept Looks For a New Home

 Verdad Gallardo
story-6

10 Best Ford Truck Engines We Miss the Most!

 Joe Kucinski
story-7

2026 Shelby F-150 Off-Road: Better Than a Raptor R?

 Brett Foote
story-8

2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

 Michael S. Palmer
story-9

10 Most Surprising 2026 Ford Truck Features!

 Joe Kucinski
Old Feb 3, 2008 | 09:07 AM
  #9  
Clint40's Avatar
Clint40
Senior User
Joined: Feb 2005
Posts: 416
Likes: 0
From: Mid Michigan
Originally Posted by 62trvler
Clint40, Did you have a dealer perform the work or some independant? That far along and I might be thinking of a BTS tranny. I need to find my build date first.
I had an independent do mine ( Sure Shift Transmissions of Kawkawlin Michigan) and I highly recommend him. Brian is the owner and has had 25 years of nothing buy trannys and does an HONEST and PROFESSIONAL job. He and I raced against each other many years ago on the local roundy round track and was recommended to me by many people before I made my decission to get it done there. He has done many of these fords for local construction companys and so on and knew excatly what I needed when I bought it in for a test drive. I delivered it on a Monday and it was done on the friday of the same week. My trans shifts so nice know that if you guys were to try it you would have your done just because , whether it needed it or not.
 
Reply
Old Feb 3, 2008 | 11:01 AM
  #10  
Tenn01PSD350's Avatar
Tenn01PSD350
Post Fiend
Joined: Feb 2006
Posts: 11,892
Likes: 2
From: Middle Tennessee
Originally Posted by hrhankypoo
My trucks build date is 01/01 so it did have one from the factory.
You need to look at the tranny data plate on the side of the tranny for the build date, not your truck build date as they differ. The tranny is likely to have been built prior to the truck build date unless it has been replaced.
 
Reply
Old Feb 3, 2008 | 08:16 PM
  #11  
greagin's Avatar
greagin
Elder User
Joined: Apr 2005
Posts: 690
Likes: 0
From: Greenwood, SC
my wifes went out at 180K about three months ago.
 
Reply
Old Feb 3, 2008 | 10:14 PM
  #12  
mueckster's Avatar
mueckster
Lead Driver
20 Year Member
Photogenic
Photoriffic
Shutterbug
Joined: Jun 2003
Posts: 8,298
Likes: 25
From: Damon (South East Texas)
When I rebuilt my trans at 128k, the mechanical diode was still in good shape. The center support bearing, for the rear of the overdrive planetary, came apart. This little $9 bearing was the cause of my trans woes. The "diode" is a ratchet type one-way clutch and the replacement is a sprag type. I had to replace the direct clutch drum also to retrofit the clutch. But, I saw recently, there is now a replacement for the "diode" that allows you to reuse the original drum. This saves you a couple of $100.
I beefed up my trans with more and a better grade of clutches, 300M input shaft, and a triple disc billet converter. I also installed the TransGo reprogramming and converter lock-up kits.
 

Last edited by mueckster; Feb 3, 2008 at 10:32 PM.
Reply




All times are GMT -5. The time now is 09:49 AM.

story-0
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-1
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE
story-2
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE
story-3
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

And it might be even better than that.

By Brett Foote | 2026-05-18 19:26:42


VIEW MORE
story-4
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

Slideshow: Does lowering an F-150 Lobo RUIN the ride quality?

By Michael S. Palmer | 2026-05-18 19:20:37


VIEW MORE
story-5
Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Slideshow: Ford's bizarre fishing-themed Explorer concept has resurfaced after spending decades largely forgotten.

By Verdad Gallardo | 2026-05-12 18:07:46


VIEW MORE
story-6
10 Best Ford Truck Engines We Miss the Most!

Slideshow: The 10 best Ford truck engines we miss the most.

By Joe Kucinski | 2026-05-12 13:09:47


VIEW MORE
story-7
2026 Shelby F-150 Off-Road: Better Than a Raptor R?

Slideshow: first look at the 810 hp 2026 Shelby F-150 Off-Road!

By Brett Foote | 2026-05-12 12:50:07


VIEW MORE
story-8
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

Slideshow: Everything You Need to Know about the 2027 Super Duty Carhartt Package!

By Michael S. Palmer | 2026-05-07 17:51:06


VIEW MORE
story-9
10 Most Surprising 2026 Ford Truck Features!

Slideshow: 10 most surprising Ford truck options/features in 2026.

By Joe Kucinski | 2026-05-05 11:17:22


VIEW MORE