I posted about a month ago about my tranny acting strange and not downshifting when stopped and was taking off in 3rd gear.

After a day or so it cleared up onits own and worked normal until yesterday.

It started slipping again, only this ime I cannt turn off the OD. When I turn the OD off, the truck still shifts from 3rd to OD and the TC does not lock up in 3rd, but it does lock in OD.

In other words, when I stop and start the truck takes off in 3rd with the TC slipping like crazy, at 45mph it shifts into OD and the TC locks up and it runs fine.

The truck pulls fine in both 1 & 2 when selected manually.

The last time I posted about this someone suggested I check the alignment of the arrows on the shift linkage, but I did not check that since it started working fine the next day.

Maybe I can start there, but would linkage adjustment prevent the OD Off button from working?

I do have a TW chip, the OD light is NOT blinking, the speedo is working noramlly and so is the cruise control, so I assume I can rule out VSS issues?

Thanks in advance for any ideas or suggestions.

ra

 

When mine was acting up , there was a break in the wire to the VSS ..

 

OK, heres an update.

After searching the forum I checked the following this morning:

1. Removed steering column covers and checked the 3 small wires going to the OD off switch for breaks. Wires looked OK.

2. Checked wiring on the transmission. I unplugged the electrical connectors from both sides of the tranny, inspected the wiring harness, lubed with Vaseline and re-connected.

3. Removed the VSS, there was no metal shavings of any kind on the VSS. I wiped it off and re-installed. Add vaseline to the connector.

Test drove the truck and there were no changes in the condition.

Here are the symnptoms again, please, I know someone on this forum has to have seen this before:

1. Truck does not downshift. When taking off the truck stays in 3rd and slips the TC.

2. With light throttle the truck gets up to 45 mph and then shifts into OD, even when the OD is turned off and the light is on, the TC locks up in OD.

3. I mashed the accelerator pretty hard at about 35 mph and the tranny upshifted into OD and the TC locked.


I am going to town later today and plan to pick up a new VSS if O'Reilly's has them just in case there is something there, however, the speedometer is working flawlessly.

Does anyone have any ideas why the OD will not turn off?

I didn't see any way to adjust the linkage, but, I know sometimes something gets out of sync and causes the romp-romp at start up when truck is in neutral instead of park, maybe something needs adjusting that I don't know where to adjust?

Come on guys, I need my truck to pull a trailer on Monday, so throw any thoughts you have my way please.

ra

 

If it was me I would remove the chip to eliminate it from the equation.

 

I will try removing the chip tomorrow.

It is a 3 position chip with different shift points in each setting and I did try the other two chip positions and it did not change the symptoms.

But, I will try to remove the chip altogether tomorrow and see if the chip is the culprit.

Thanks,

ra

 

OK, curosity got the best of me and I couldn't wait until tomorrow to unplug the chip.

I took the chip out and the problem still persists.

Can O'reillys or Autozone pull codes from the truck?

I am going to town later today and I could swing by and have it scanned if they can do it?

Thanks

ra

 

Have you disconnected the batteries to attempt a PCM re-set?
How old is the fluid and filter?

 

I have not disconnected the batteries.

I will try that tomorrow afternoon.

The fluid and filter is 3 years old with 40K miles on it.

I also bought a new VSS while in town today, we live 30 miles from town so its not easy to run in and get parts multiple times per day.

I will disconnect batteries and install the new VSS and post the results tomorrow afternoon.

The fact that I cannot turn off the OD really has me scratching my head. I have done multiple searches and cannot find any other threads which discuss this issue.....

Thanks again for the replies,

ra

 

Update on issue.

OD wouldn't turn off and 3rd gear starts, problem solved.

Replaced range selector on the side of the tranny.

$80 and back to normal.

 

Glad you got it fixed. Pretty simple...just hard to find lol.
Thanks for posting the 'fix'. The next guy with those symptoms will appreciate it too
Green beans sent

 

Good fix! X2 on posting the resolution. Thats one to save for future use.