This ones got me puzzled. Customers 01 f250,7.3,auto tranny, 59,000 miles,
stock, no tuner,nothing. When you're sitting in park or neutral engine accelerates normally. Put it in reverse, and it takesoff OK. Put in drive and it won't hardly get out of its own way. the engine does'nt rev up like the trannys slipping, it acts more like its not dropping into 1st gear kinda like it does when you put the tranny in manual 2nd. its not the accel pedal nor is it the EBPV. It has no current codes or history codes or feeze frame data. like i said its got me scratchin' my head. Ponder on this and let me know whatcha think thanks Barney

 

With an 01 good chance of having that diode clutch in there.

Does it act normal if you put it in 2nd and pull off?

 

I'm going to try that tomorow. It just came to me tonight, as I was recapping the day. You mention a "diode clutch". What is it, and what does it do? Thanks

 

Alan you make me think you are as sharp as a tack.

 

I used to think that also. After his help with my truck, I am now convinced of it.

 

Shukks guys, thanks.

bfife
Ford tried to improve the 4R100 in the 01 trucks by switching to a mechanical diode clutch instead of the tried and true sprague assembly. it lasted all of 4 days on the assembly line before Ford realized they screwed up but it took 6 months to retool and go back to the sprague.

 

is there a way to determine if a 01 truck has the diode? Is there a fix or mod for the diode disaster?

 

Tranny build dates between july 2000 and feb or march 2001. A tranny rebuild is required to fix it so most just drive it till it implodes and then address it

 

OK truck build date 9/00. Talked to customer, he had the tranny replaced Nov 05. Good rebuilder, upgrades included billet T/C and billet input shaft. There is no difference starting out in drive or 2nd or 1st. engine seems to bog and truck slowly pulls away.

 

Can you get the truck up to speed, like 50mph??

 

Yes, it will go up to road speed. Shifts good and solid. it just takes forever to get rolling.

 

how are the air and fuel filters?

 

Does this describe your issue
https://www.ford-trucks.com/forums/5...-for-sale.html

 

the air and fuel filters are all new. the fuel pump is drawing only 6 lbs vaccum when tested between the tank and the fuel pump, so the intank "sock" is not plugged. Ok, the weather and roads cleared up alittle this afternoon and I got sometime to do some road testing. It will get up to road speed. its just starting out in 2nd gear. After 10 miles it begins to shift normally. stop and it drops to 1st like it should. put it in manual 2nd and it starts out like it was before. back to drive or 1st and its normal. I'll check again in the morning. seems to be a repeatable problem. I'm wondering now if its a mechanical problem such as a sticking valve or if its an electrical problem like a intermitant soliniod. thanks for all of your help, I'll keep posting with test results. til we get it fixed thanks Barney

 

does it act like an engine problem - mash pedal and rpms slowly come up (chugging) or do the rpms come up and the TC/Tranny slip and not get the power to the wheels?