Explain to me how the 47re shifts

[Great work!]

Old but a good article.

 

I've noticed that the governor transducer voltage goes up from about .5V at zero mph to about 4.5V at 45mph so all the 1-2 and 2-3 shifting is done at 45 ish OD shifting takes over after that. The PCM uses the speed sensor in the transmission for shifting not the rear end, not sure about OD and TCC. The sensor in the rear end is used for the speedo and anti lock, that way the transmission will still upshift with out red lining the motor in 4 wheel low range and the speedo will be correct. 

 

I've also noticed the PCM causes a bump in governor pressure when the throttle is opened past about the 1/2 to 3/4 position. This makes the transmission think the vehicle speed is a little higher than it actually is, so it holds the gear longer. I'm guessing that was done on the diesel so it can lug more than the gas version without being overly downshifting. 

[Evan]

Yes very good.

 

Great work 

Question for you. Just did my 47refresh no issues on assembly transmission full refresh, seals, bushings, steels fibers, all eletronicals.

 

I did have issues with nuetral safety switch but resolved that now i have ni cruise control. Indicator turns on on cluster but doesnt set.

 

Speedometer does work everything works but cruise control. Cruise control did work before pulling transmission out of truck.

 

I realy like cruise control kinda at a loss.  Only issue was nuetral safety switch so my mind keeps going back to it.

On first start up i jumped the plug with a paper clip then figured out i wasn't making contact on switch to switch lever inside pan. 

 

Thanks for your response.

[Great work!]

Check the vacuum lines. The battery causes the line to get brittle and crack.

 

Happened on my truck. Does the backup lights work.

[Evan]

Will check out the vacumn lines and check if back up likes work. I thi k back up bulbs blew 10 years ago or atleast 1 lol.

 

I have fixed one vacumn line by the battery quute a few years ago. Maybe it rebroke

[Evan]

Got to thinking about neutral safety switch. I rememberd truck used to start in drive.

 

It now currently will start in reverse, and second gear. Wont start in drive or first.

 

 

 

Tomorrow im going to unplug safety switch jump the prongs and see if cruise control then works with the switch  bypassed

[Great work!]

Sounds like the plastic bits that snap into the rooster comb broke. Might have to drop the pan and take a look.

[Evan]

Its been messed up since i installed valve body on the bench. Maybe partly because i had sensor removed when installing valve body.  

Being on the bench made it to easy to get it wrong i guess 

 

Plastic bits were still intact on rooster comb

[Great work!]

If the little metal tip of the neutral safety switch makes any contact with grounded metal: IE the rooster comb it will start. The plastic bit prevents electrical contact except where it's cut out in park and neutral.  The outer plunger part that has the metal *** in the center gets pressed back in reverse to operate the back up lights.

2 hours ago, Evan said:

Plastic bits were still intact on rooster comb

ounds like the plastic bits that snap into the rooster comb broke. Might have to drop the pan and take a look.b

To prevent breakage the neutral safety switch should be removed whenever the valve body is being removed or installed.

[Evan]

Lol idk do ot right i get it wrong do it wrong i get it right. Ive had tge valve body out a few times without removing neutral switch. 

One time on the bench where its easy it goes wonky.