I have just purchased a brand new, beautiful $600 ranger, and I am having a transmission issue that is throwing me for a loop.

The trans either hard shifts, or does not shift at all unless you let off the gas. If you push the truck hard at all (try to go above 65 or so) it flashes O/D off, but it also will just flash kind of randomly if do anything but baby the accelerator, and what is strange is overdrive is not off. If I get to 55-60 and press the button my RPMs consistently raise and lower.

the codes it’s throwing are (not all are trans codes but I thought I’d include them anyway)

P0732

P1751

P1756

P0455

P1309

I have tried putting in some SeaFoam transmission degunker, at the advice of a friend. It did not seem to help. The next step in my head is fluid flush and filter, then valve body gasket, then solenoids. But I am really not sure what the diagnosis is on this one. So any help is much appreciated.

 

A Flashing O/D Off light is your transmission warning light. It tells you that codes have been stored related to the transmission, but most code readers can't touch the transmission codes in these trucks. Only the higher end scanners can access the transmission codes, but some of your codes listed are transmission codes, so you apparently have a higher quality scanner.

The hard shifts are due to the transmission being in "limp home" mode due to the flashing O/D Off light. The computer is basically forcing the transmission to work in order to get you off the road. It is not meant to be driven like this.

 

Well what do you think is putting it in limp mode?

 

It was 600 bucks for a reason :)

Pull trans pan and look for damage. Kinda gives you idea how bad this transmission is and if just needs rebuild or replacement rather than trying to chase different things. If you see metal shavings, stop and dont go any farther trying to diagnosis or waste time with valve body/fluid change. I wouldnt flush with pressure machines nor use a degunker. If there is gunk and its dislodged, guess where it gets hung up...drain and fill a few times is safest for older transmission.

Youll probably need to re sync that camshaft position sensor correctly and find that evap leak while your waiting on a transmission :) Good luck!

 

I have a '99 3.0 v6, which I understand is what you own. This year transmission tends to blow out the gasket between the separator plate and the valve body.. If you pull the pan on the transmission, use a flashlight to look all around the valve body. If you see a piece of gasket sticking out you have the problem. Where the gasket fails determines what the symptoms are. Ford has a TSB on this problem and recommend a separator plate with a gasket bonded on to it as the fix..

 

Yep, the valve body had gasket issues and over time the solnoids stick and/or valves wear grooves in the body. Sometimes its best to get a remanfactured valve body with all new solnoids and a nice warranty from a reputable place. Stay away from anything under $150. I tried to go cheap and got burned twice.

If a new valve body doesnt fix it, you could have a local rebuilder rebuild the whole transmission and reuse the purchased valvebody. Although, its a crap shoot with rebuilders these days. Remanfactured transmissions are the best bet with good warranty (some even pay labor warranty). All components are touched with reman and your guaranteed a good working transmission that will probaby be better than factory put out.