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Discussion Starter #1
Hey everyone,
:help
Ok, this is going to be a LONG post, but I want to give as much info upfront as I can. I'm sure most of the 'problems' I'm describing are driver error, so thats what I want to find out what I could do better to help keep this truck as cool as possible before summer hits.

I just got home pulling a 2010 eclipse attitude 5th wheel up and down some fairly long hills. For those familiar with Az, up the beeline to Roosevelt Lake. Pretty much loaded up as much as I would normally do, except empty water tank...so maybe around 13-14K?

On the way to the lake:
Ambient temp: ~80...Little if any breeze
Highest engine temps going up: 231
Highest tranny temps going up: 220-223
Speed, gear, and RPM's: IIRC ~45/50mph, 4th and 3rd gears, holding around 2500rpm

On the way home from the lake:
Ambient temp: same
Highest engine temp going down: 235 for just a second or so
Highest tranny temp: 200
Speed, gear, RPM's: 40-50mph(only under 40 for about 2min, stuck behind a semi @ 25mph), 4th gear, holding around 22-2300rpm.

Tires: 70-75psi front, 80-85psi rear, trailer tires filled to 78 before we left cuz my little compressor wouldnt do 80!

Tow/haul: on both trips.

Good fan activation the whole trip, but a little late feeling for my taste. The truck has ~88k on the clock, dont know what oil, diff fluid as I havent done an oil change yet. But I may talk my wife into letting me switch to mobile 1 syn. early if it will help. I'm also thinking of a deep trans pan, but with that should prob. come a transgo jr, and a new internal filter too.

This experience was much improved from the LLY I came from. Stress was about half, but I would like to know what this truck is capable of and what I can do different to get that stress down to almost none. I'm not looking to win the race up the hill, and if this is all this truck is able to do, then fine with me. I just want to get this down before ambient temps get to 115+.

Before I put the trailer away, I may check wheel bearings just to be sure they're ok even though its still pretty much new.

So what could I have done better, what if any upgrades would help the situation (bang for the buck since bucks are kinda low :) ), etc...

Thanks for your help!
 

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Get a monitor to check the temps....my trucks gauge says much higher than my mini maxx plugged in my port.

Sent from AutoGuide.com Free App
 

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Discussion Starter #3
I have the insight cs and was using that for engine temp, but was using the dash digital display for the tranny temp.
 

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I pull a 16k 5th wheel Attitude and I would suggest to try letting your RPM's drop a bit...my truck pulls happily at 1600 or so. My instinct used to be to keep the revs up, but that just seemed to generate more heat.
 

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Discussion Starter #5
I pull a 16k 5th wheel Attitude and I would suggest to try letting your RPM's drop a bit...my truck pulls happily at 1600 or so. My instinct used to be to keep the revs up, but that just seemed to generate more heat.
Ok, so typically what gear are you in and what speed are you doing for reference?
 

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In drive and cruise control on at 55-58 max using the tow/haul mode. I'm in CA (trailering max is 55mph) and already got a trailer towing speeding ticket a year or so ago for 70 in a 55...it was VERY painful, so I behave now! The trans does a fine job of managing the speed/shifts and I find that even uphill, it upshifts much sooner than I would have if doing it manually and it does just fine.
 

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deleting the dpf and getting a decent tow tune via efi live will help lower engine temps pretty dramatically.
you can also add in a turbo brake feature with efi live as well.
 

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Discussion Starter #9
Yeah I know getting rid of the dpf and a good tune will work wonders. Cost is a factor, and I am saving up to do this. Wont be before summer though.

I did pm mike L for a quote on price of a trans cooler. That obviously would delay even further efi live, but something in the meantime would be beneficial and thats seems like a good upgrade.

Next tow I'll just leave it in tow/haul and let it do its thing and see what happens like bblitz said also.
 

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Get a oil temp gauge for that CTS asap and monitor those temps...........I would look into an aux oil cooler.
^^^Listen to Brian. :thumb
1st thing, get that Probe! (easy install)
You'll be shocked to see how hot it gets down low on those runs.

2nd thing, lower those RPMs (1800-2100 is the sweet spot).

Once you see how hot your oil is on that run, look into the aux oil cooler before considering the trans cooler update. Pull that heat from the source (oil) and your cooling stack load will be reduced, lowering trans temps and ECTs.

Some ideas:
Engine Oil Cooler DIY
 

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Get a oil temp gauge for that CTS asap and monitor those temps.


I would also get a Mike L 6 speed cooler.


Lastly, If you tow quite often, I would look into an aux oil cooler.
This guy speaks da truth ^^.

You will be surprised at how hot these babys get in the bottom end.

I know it has been mentioned, but lower those RPM's. You will get better fuel economy and lower temps overall. :thumb
 

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Discussion Starter #13
Let me preface by saying I do not wish to start up another oil cooling vs. coolant cooling argument, and I dont mean to sound rude or arrogant.

Unfortunately I am all too familiar with the oil cooler idea. I'm also too familiar with the aux cooler for the coolant. I've read for hours on end on each, and why it happens, etc... If I were to chose one of those routes, I would go aux rad. simply because I still have it from my LLY. I've watched oil psi drop off at high temps, I've backed out of the throttle way far only to watch coolant temps continue to rise till I'm tempted to pull over and stop even though I knew it would make it even worse. All this coupled with the headgasket time bomb looming is why I made the move to get away from the LLY. I'd hate to have all the same problems, and go back to all these add ons with a newer more expensive truck.

I know I'm going to burn in hell for this: but I could have avoided this again bought a powerchoke,LOL. But seriously my father in law has the 7.3 and his trailer is 18K and never has any issues pulling that big boy, cruise set to 50-55 same hills. I've always prefered GM though.

Back on topic:
Next pull I'm going to try and let tow/haul do its thing and/or keep RPM's lower, and if it starts to get out of hand depending on which way it goes consider further options. I may hold on to the aux. cooler till it gets hotter outside, and if need be I'm sure it can be made to fit 'fairly easily' LOL.

It sounds like from what most replies have been is a lot of the issue was on my part anyway.
 

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FWIW, I just pulled my 16K+lbs 5th wheel (3300# pin weight) toy hauler about 300 miles this past weekend with 1/2 a bed full of firewood and a large loaded cooler, full loads of fuel/water, myself, passenger, and the backseat full of misc stuff from San Diego to Plaster City and back. Left it in drive with tow/haul on and the cruise set at 58mph, with the exhaust brake enabled. Engine temp stayed rock solid at 210, rpms at 1600 with it making an occasional downshift and bringing the rev up to 2100-200 as needed, tranny temps hovered around 135. On one of the steepest/longest westbound uphill grades, it downshifted and came up to about 3200rpm for a couple of minutes, and pulled hard with the EGT's up to 1000degF a few times. I don't even recall the aux/hi speed fans coming on at all. I think the temperature was in the mid 60’s at the higher elevation (about 4000 feet according to one sign I remember seeing), but we definitely started out in the upper 80's or so. It purred away happy and averaged 10.3mpg round trip. The truck has about 1,200 miles on it now. I only had 2 times where I got behind slower semi-truck traffic and had to wait for an opening, and with better planning I could have avoided that as well I'm sure. When I was able to pull out, I had plenty of power to pass easily on the uphill sides. It held the speed beautifully uphill and downhill. Hope this provides some reference...
 

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Definitely get something to monitor with besides the factory crap, mine says the ect is 210 when its really 180.
 
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