68RFE Questions

I have a 2012 RAN 2500 fully deleted by Ray at DRD.

Love my truck and the tuning.

The other day my truck went into limp mode and wouldn't go out of 4th gear.

Checked the DTC and had P0846 - Trans fluid pressure sens/switch B circ range/performance.

Got it home and did some reading and ended up changing the line pressure sensor.

The truck ran fine for 2 days and then went to limp mode again.

I had the same code as before and a new code of P0934 - line pressure sensor circuit low.

I had the line pressure check with a gauge and scanner and both read around 175-180 psi.

I Spoke with Ray and he said in my tune he increased the line pressure to 170 psi.

Could I be getting the code due to my line pressure exceeding 170 psi?

If so could it be caused by cross leaks in the valve body?

I have been looking at the ATS valve body upgrade if that is the problem.

I don't want to replace it with a OEM since they seem to be weak.

Friend, the tuning doesn't change, and hard parts all always 99% of the problem.

The 170PSI makes the trans have a crisper shift, and the stock valve body can handle that with no issues.

It sounds like issues are the line pressure sensor on the transmission or a problem with the valve body.

God bless,
igotacummins

Quote:

---

Originally Posted by Osterhus33

I have a 2012 RAN 2500 fully deleted by Ray at DRD.

Love my truck and the tuning.

The other day my truck went into limp mode and wouldn't go out of 4th gear.

Checked the DTC and had P0846 - Trans fluid pressure sens/switch B circ range/performance.

Got it home and did some reading and ended up changing the line pressure sensor.

The truck ran fine for 2 days and then went to limp mode again.

I had the same code as before and a new code of P0934 - line pressure sensor circuit low.

I had the line pressure check with a gauge and scanner and both read around 175-180 psi.

I Spoke with Ray and he said in my tune he increased the line pressure to 170 psi.

Could I be getting the code due to my line pressure exceeding 170 psi?

If so could it be caused by cross leaks in the valve body?

I have been looking at the ATS valve body upgrade if that is the problem.

I don't want to replace it with a OEM since they seem to be weak.

---

Sounds like the beginning of the end for your valve body.

My 2012 threw the p0871 code while towing last year.

I changed the pressure sensor in a parking lot and thought I fixed it. Next time towing same thing.

Apparently cross leaks in the valve body can throw different codes.

New RevMax valve body and filter screw fixed it. Now's the time for a new pan with a drain plug also.

My tuning is set to 250 psi trans pressure by DRD.

Disclaimer: Not saying this is your exact problem but mine started as a 'pressure sensor problem'.

Sent from my SM-G950U using Tapatalk

How many miles on the truck and what kind of history/current driving conditions has it had?

With the information known it does sound like a new VB could be a good route vs. changing sensors and chasing that way.

Yeah I'm not saying the tuning is bad.

The tuning is great.

Just wondering if it sounds like I am having cross leaks in the valve body since my line pressure is above what the tuning is set for.

If it does sound like that then I am going to get a new valve body for it.

I have a little over 133000 miles on the truck.

Mostly daily driving, but I do occasionally tow with it.

I always drop to the lowest tune setting when towing.

Changed the trans filters about 25000 miles ago.

Any updates on your problems?