oil temp with twins
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I saw the thread on DP when you bought it. I crapped my pants for how much you got it for... 
:rofl: :thumb:
:rofl: :thumb:
Damnit!! I'm sold on the theory, cooler and guage.
This makes it much more difficult to close my eyes and not spend the money! Damn you for composing this write up!!! :rofl:
Did you use a oil filter adaptor or a thermal bypass? If you didn't use a adaptor how did you hook your lines up? pics
I saw the thread on DP when you bought it. I crapped my pants for how much you got it for...
yeah, except now I want to delete the stock oil cooler and just run the KB one, mounting it somewhere with fans on it. The truck doesn't get driven on the street much, and when it does, it wont be using all of its potential.
After a few weeks of testing, here are my results..
I bought a "new used" Killerbee cooler from a member local in AZ. Before I had the cooler, on the hills my oil pressure would flucuate between 35 and 65psi. I knew it was because of the oil heat from the twins. I didnt put a oil temp gauge in till it cooled down some ( was 115* outside air temp). My gooseneck is 4500 lbs or so, not a heavy load, but puts some weight behind the truck for a good test. Anyone who lives in AZ knows the hills between PHX and Flagstaff, the highest oil temp I saw going 60-65mph mph up the grades pre OEM oil cooler was 274*, at this time the oil pressure gauge was doing the :dancenana:
Around town was a different story; coolant temps follow the oil temps, untill I get on the freeway, then the oil temps start to climb; unloaded. Normal oil temps at cruise @ 65 were about 195-215. Coolant would remain at 187-190.
I decided it was time to invest in a cooler. If my oil temps are out of control towing a unloaded trailer what happens if I load 12k behind it...
Cooler installtion was cake, mount the huge cooler, and plumb the cooler lines form the oil filter assembly. New cooler took a little over 3.5 qts, so I throw in 14qts on a oil change and call it good. Took me 2 hours. Cooler measurements are 28" long, 7" tall and just over 4" thick, it's a huge cooler...
Retested the route I took a month earlier, outside temps did drop about 15* or so, but the same hills at the same speed, here is the oil temp crusing up the hill at 60mph, pulling the same trailer.. Sorry camera is a bit out of focus.
I have regained control of my oil temps and oil pressures. Ive gained back a few PSI at hot idle, and I would say 5-8psi at 2000rpm cruise. This lower oil temp allowed my to run a max gauge of 250* instead of 300*
Coolant temp is more stable, since the OEM oil cooler isnt working so hard offloading the oil heat into the coolant. Oil temp comes up slower, as well as the coolant. I do not have any mor eoil pressure and flucuation issues, which was my main concern. I think any sort of engine oil cooler should be on every twin'd duramax, simply because of this issue. We only have 10 qts of oil to cool a lot of the engine, and a undersized cooler to deal with it. If you dont have a oil temp gauge with twins, I would higly suggest putting one in. Takes 20 mins to install one using the hex plugs in the oil filter assembly.
Brian,
these are exactly the results I was seeing.
I have since bought an lly with single stock turbo that I will be twinning soon. I just installed a cooler with thermal bypass at the filter. The cooler I am using is a setrab (same as Mike L fuel cooler) with dual fans. I have a stock truck as of now and I have seen a big improvement in oil pressures with a completely stock single turbo truck even driving empty in colder temps (15-40* outside temps). I think this just goes to show how inadequate the stock oil cooler is even on a stock truck. I havent even hooked up the fans yet, but it is certainly bypassing some oil to the cooler as its always warm and I gained about 2.5 quarts capacity. I mounted mine on the frame right behind the torsion bar crossmember similarly as to how a lift pump would be mounted.
everyone running twins NEEDS an oil cooler and those running any power over stock should seriously consider it, I imagine it would be an even bigger concern on lbz's/ lmm's with weak pistons, the better you can cool the pistons that less chance of them cracking and smoking hot oil isnt going to help the piston issue.
Did you use a oil filter adaptor or a thermal bypass? If you didn't use a adaptor how did you hook your lines up? pics
That's what I was wondering. I thought that cooler came with a thermostat filter adapter
:hug:
I used a oil filter adapter, no thermostat, as soon as the engine is running it's sending oil to the cooler. When I changed my oil I had zero oil pressure for 5-6 seconds, which is no worse than normal.Did you use a oil filter adaptor or a thermal bypass? If you didn't use a adaptor how did you hook your lines up? pics
Line is -10 AN.
Picked up a 3/4 drain cock from Cat
Adapter
Feed/Return lines. They are pretty close to the PPE manifolds, but with some more thermal wrap on the lines it will be fine, I need to pick up some more
I ran the lines around the steering box and above the upper mount for the front differential. No where does it rub on anything. :thumb:
Adapter
Feed/Return lines. They are pretty close to the PPE manifolds, but with some more thermal wrap on the lines it will be fine, I need to pick up some more
I ran the lines around the steering box and above the upper mount for the front differential. No where does it rub on anything. :thumb:
Looks good man I like it. I'll have to look into doing this before the summer camping trips over the pass begin.
Looks good, witch oil filter adaptor did you use? That cooler is huge I looked around and so far nothings close other than being really wide.
Just to do it, I unhooked the OAT sensor in front of the radiator stack and placed it behind the oil cooler to see what the air temps were behind the cooler at 60mph. Outside air temp was 56-65 and the rearview mirror read in excess of 112* the whole trip on the freeway. Very impressed so far. :thumb:
Quick update to this, I've put about 2500 miles on this cooler since install, no leaks, and max oil temp Ive seen is 190* pulling a 30' Big Tex gooseneck up to Flagstaff, AZ, many 5-7% grades along the way. Trailer is about 5k empty. Around town I only see about 175* coolant temps, and 180* oil temps. Its also around 60-70* outside here as well. Changed the oil after I put the cooler on, and 2500 miles later, still golden . :thumb:
