68RFE High Line Pressure

Hi. I bought my 2012 2500 Cummins used back in October.

I've put lift and 37s Toyos on it since then. The guy before me had 5th wheel hook up there's still some hard ware in the bed. Every question I asked the sales man bout the truck he had no clue. (Truck sold it self)

I did a full delete few days after I got it. I'm running a raceme tuner.

When ever I put the hammer down 80% to 90% throttle it when I'm passing someone on 2 lane highway I see high line pressure I've seen 192PSI 198PSI even seen 204PSI now I thought the 68RFE transmission was stock but I didn't think a stock pump would do much over 185PSI.

So I'm pretty confused. I truly can't complain about how it shifts. I do love the converter lock up in 4th just feeling all the power getting to the ground LOL.

So should I think the Tranny had a little work done to it? I plan on driving the same witch is ***** footing around but let's face it sometimes u gotta feed a lil speed to your ride. So what do u guys think stock 68RFE or lil work done to it?

Thank you in advance.

Do you know if the RaceME Ultra you have is running stock tunes?

Are you watching the desired line pressure or the actual? Factory you will see 160 to 180 with occasional spikes til it's regulated back down. What's the mileage on your truck

Hi............ The milage on my truck is a 105k. I have set so im actual line pressure.......... No not runningThe tune I run is the 120hp, 1850bar, 29timing, low torque, turbor quick spool. I would totally run a higher HP tune and wild torque tune because I did run that for a month or so and got the best fuel mileage like 24 to 26mpg on the highway& 20 to 21 in the city with 37x13.50 Toyota Tires that's pretty damn good. I just got worried that I was shorting the life of my 68RFE way to much. Thanks guys for ur in put & time.

I would take it easy with those 37" tires. Especially of the line. What is the axle ratio? 3:42 not good, 3:73 okay, 4:10 best. Not trying to be mean here, mind you, just trying to not blow the trans with those large tires. ;)

Just for comparison purposes, i'm also fully deleted, running DRD tunes (w/tranny tune). completely factory otherwise. 35" tires, no lift, only 2" level in front. 2013 2500 4x4. I normally run a 120hp tune.
I monitor actual and desired transmission line pressure and i will often see spikes up over 200psi... like 204'ish on actual, when desired is 170-185. but it's only temporary. It happens so fast, I only know it's climbed that high because the max reading gets stored. 99% of the time, actual and desired are equal (I think this is the most important factor). I get into it on occasion, but i'd say 75% throttle is about as hard as i hit it and VERY rarely from a dead stop. The above spike does not seem 100% correlated w/throttle %. in fact I've noticed the higher pressures under normal driving conditions when the transmission oil is not yet fully up to temp (i DO NOT romp on it if the truck is not fully warmed up). Once everything us up to operating temps, my actual may barely overshoot desired pressure. And like you I have no issues w/how the transmission shifts or performs.

I wanted to thank you guys guys for taking time giving me some insight on what's going on. Oh I'm running 3:73 gears. I've also started to monitor my actual and desired line pressure. I've made sure since I got my truck not to hammer on it tell its totally up to temp and I dont think I've mashed on it from a dead stop it's been while I was rolling. I've been treating right I know my wife says I spend more time with the truck than her LOL. Only showing off a few time. Like I said mostly when passing on 2lane highway. Again thanks for all ur info it's much appreciated.

Gonna threadjack a little here, i was driving today through the smoky mountains and on my actual, i got a spike to 215psi. Running Ray’s 90hp tune, with what should be line pressure stepped up to 180 on 35” tires and 3.42 gears.

Actual pressure was usually hovering in the 130-170 range most of the drive, but that Max value kinda got me concerned.

Am i understanding correct, that temporary overshoots on actual pressure are acceptable? I wasn’t watching desired unfortunately

Quote:

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Originally Posted by ViperCummins

Gonna threadjack a little here, i was driving today through the smoky mountains and on my actual, i got a spike to 215psi. Running Ray’s 90hp tune, with what should be line pressure stepped up to 180 on 35” tires and 3.42 gears.

Actual pressure was usually hovering in the 130-170 range most of the drive, but that Max value kinda got me concerned.

Am i understanding correct, that temporary overshoots on actual pressure are acceptable? I wasn’t watching desired unfortunately

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Normal. Line pressure can spike during a shift and go as high as 250 psi in reverse on a stock transmission.

Ray,
Double R Diesel