Tranny diode?
Hook it, I'll pull it.
Joined: May 2007
Posts: 15,037
Likes: 4
From: Grand Lake, La.
Be careful with that -- guys with supposedly "safe to 500HP" forged rods have daylighted their blocks with barely over 400. Then there are others with PMRs running 400ish with no problems. I'm gonna stop at 375ish here.
Don't worry about it if you're just getting an Edge. You'll be lucky to be making 300.
Don't worry about it if you're just getting an Edge. You'll be lucky to be making 300.
Post Fiend
Joined: Apr 2007
Posts: 7,241
Likes: 1
From: Powder Springs, East TN
Unless you can get an edge dirt cheap then I wouldn't get it. If you want to ride in a DP Tuned truck I can drive that way oneday and give you a ride or Scott Crum71 can come down and give you a ride we both have similar mods. As for the tranny I forget the build dates but it was only 6 months they had the Dioded trannies.
Posting Guru
Joined: Sep 2007
Posts: 1,715
Likes: 2
From: Seneca, SC
Unless you can get an edge dirt cheap then I wouldn't get it. If you want to ride in a DP Tuned truck I can drive that way oneday and give you a ride or Scott Crum71 can come down and give you a ride we both have similar mods. As for the tranny I forget the build dates but it was only 6 months they had the Dioded trannies.
Lead Driver
Joined: Jun 2003
Posts: 8,298
Likes: 25
From: Damon (South East Texas)
I upgraded from my mechanical diode at 128,000 miles. It was not giving any problems either. I replaced it as part of my rebuild (failed center support bearing) and to upgrade the drum to a better clutch pack. Clutches stil looked brand new at the time. I just wanted to beef it up for future mods and for towing.
Post Fiend
Joined: Feb 2006
Posts: 11,892
Likes: 2
From: Middle Tennessee
Post Fiend
Joined: Apr 2007
Posts: 7,241
Likes: 1
From: Powder Springs, East TN
05 Front end or throw some tougher rods in and keep trucking.
Post Fiend
Joined: Feb 2006
Posts: 11,892
Likes: 2
From: Middle Tennessee
Mark, do you know what the reason was behind that design? I am curious what advantage someone must have thought that diode might have?
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Hook it, I'll pull it.
Joined: May 2007
Posts: 15,037
Likes: 4
From: Grand Lake, La.
Butt-Head
Joined: Apr 2004
Posts: 9,457
Likes: 2,938
From: Reed Point, MT
If anyone is still interested, the "mechanical diode" was the replacement for the one way roller clutch previously (Intermediate one way clutch) used in the E4OD and 4R100s. After Ford found out that the diode wouldn't work in the gasser trucks (they exploded when shifted at 5300 RPM), they decided that they should stick with the proven and slightly more robust design. It is a mechanical device that allows rotation in one direction but not the other. It is used for the 1-2 shift when in drive range. When the "diode" was used, it replaced the roller clutch with a sprag that is inherently weaker. High power/high RPM 1-2 shifts are what kills the intermediate one way in the diesels.
Frmr Ford Trans Engr
Joined: Aug 1999
Posts: 24,739
Likes: 2,669
From: SE Florida
The gas engine trucks blew up the diode at 4600 RPM if the driver lifted his right foot just as the WOT 1-2 shift started, then put it right back on the floor. The person that discovered this was able to do it on 100% of the trucks he tried it on. That's why they left it in the diesels, they couldn't run 4600 RPM.
Hook it, I'll pull it.
Joined: May 2007
Posts: 15,037
Likes: 4
From: Grand Lake, La.
Cost.
The gas engine trucks blew up the diode at 4600 RPM if the driver lifted his right foot just as the WOT 1-2 shift started, then put it right back on the floor. The person that discovered this was able to do it on 100% of the trucks he tried it on. That's why they left it in the diesels, they couldn't run 4600 RPM.
The gas engine trucks blew up the diode at 4600 RPM if the driver lifted his right foot just as the WOT 1-2 shift started, then put it right back on the floor. The person that discovered this was able to do it on 100% of the trucks he tried it on. That's why they left it in the diesels, they couldn't run 4600 RPM.
Mark, what does that mean for our trucks? With the torque we are running, does that make a difference with the Diode trans? I want to know what to expect with my tranny.