Over my last trip towing I wanted to ask you guys a few questions regardings EGT's and towing. First off I am aware that having the pyro in the downpipe is not ideal and I have a second one showing up on tuesday to go in the manifold. I wanted your opinions regarding a stock tune vs other settings and which is safe when starting to run hot. I was pulling a very small 8k lb enclosed trailer half the size what I normally tow on relatively flat ground with a few gradual hills. Here are the number I saw with a tail wind at different tunes at 65 mph at 50-60 degree ambient temps:

stock: 900-1000+ cruise
80 tow tune: 700downhill -950 cruise

Coming home the next day with a 20-30mph constant head wind

stock: 1050+
80 tow: 1000
100: 850-1000
140 agressive: 800-950 saw 1000 a few times but ran noticeably cooler

I was driving 65 mph at about 2300rpm in 5th. If I dropped down a gear to 4th slowing to 60 I was sitting at 2800 rpm and would lower my EGT's about a 100 degree, but the truck felt absolutely gutless at that rpm. Its like there is a very noticeable sweet spot in the rpm and once you go over that the torque curve falls on it face and it pointless to be holding the pedal down any more. FYI I never got to 3k.

I am fairly new to modifying diesels but from all the threads I have read I am towing on the border line if not over of running too hot. I would try to get it cooled down as fast as I can without sticking at any of the high points for too long but I thought this was sort of odd that the truck was running much cooler at a higher tune. I have used the same year bone stock trucks at work towing much heavier in the rockies and never knew about EGT's till buying my own and modifying. I just thought the results were very alarming considering what we put the work trucks through, granted they have never had any sever problems besides cold starting in the last 7 years. and towing a 10k chipper and 16k loaded goosenecks much more than what I was dealing with.

I actually called my mechanic mid trip and asked him what he thought and he was the one who suggested to bumping it up to highest setting and give that a shot. I was really confused why the truck would run cooler at this setting than the stock setting. Its the last thing I would have guessed to do. This is also not a ton of weight by any means and when I tow my trailer it will be anywhere between 10k and 12k. I bought this truck solely for towing but am sort of timid to push it since the motor is a low mileage motor and I want to keep it running for a long time.

I know lugging a diesel is going to make it run hotter, also having a high setting on the tune will give more power there fore require less pedal, but considering all that, if I were going to take the chip out and tow this fairly light load on the stock tune on slightly more aggressive terrain I could see the EGT temperatures go well above the safe zone.

My up pipes are not leaking...

my boots look fine, but should test for leaks before the next trip


Your thoughts and suggestions?

I picked up a 6.0 cooler on the way home as well... that is the next project after the new gauges. The guy gave me the plastic tubes but I'm guessing they are useless and just necking down a 3 inch to 2 will be easiest. I am really curious what is going on with the boost and need some hard numbers off a boost gauge to make sure that is not an issue.

Anyone have a spider hanging out in the garage they do no want

 

What plastic tubes are you talking about?

I'm not gonna comment too much on the temps besides they seem kinda high, for where the gauge is mounted, until we get some definite results from your new gauge.

 

That's odd. My egt's go up when i crank up the power with my chip

 

I say you wait to make any major changes until you get that other EGT gauge in there to verify that you're running that hot. It would be a shame to get all excited only to find out that your gauge or thermocouple is bad.

 

EGT's went down cause the truck had to work less hard to move the load.

Tow Tunes are a timing change, and help with EGT's/fuel.

 

They were the stock plastic intercooler tubes that came off the 6.0. He bought a Banks cooler and pipes and gave me the stock stuff.

I agree, I don't think the thermocouple is bad, but I am very curious to see what is actually happening at the manifold because they do seem very high at the down pipe.

Thats what I thought would happen.... especially at the agressive tune setting. I understand the idea behind changing the timing to run cooler for the tow tune, but when my mechanic told me to try the highest setting and see if it ran cooler and it ran drastically cooler I was really confused. I did not expect that. He told me he tows with the highest setting on his 6.0 all the time, and thats all he uses when he has a load behind him. Has had a chip on the truck since day 1.


Agreed

I guess in the long run that's what I got out of it. Like I said for guys running around with bone stock trucks, I feel they must be running super hot compared to having the truck with a chip, however the story I always hear is that guys melt down motor BECAUSE they got a chip... and ran hotter. That is the opposite what I'm seeing happening. Unless my stock tune is really effed up and the truck just runs that hot on it.

I have towed this trailer before with my Boss's truck and pretty much had it to the floor most of the time through the mountains. I just do not understand that if these motors run this hot stock, then how the hell are his trucks still running. both with 250k now and have always had around 10,000 lbs or more behind them over the last 7-8 years towing with the pedal close to the floor the majority of the time.


Like I said all I can go off of right now is what I am seeing on the gauge.

 

They cannot get hot enough stock.

They design them to not melt down unless your towing over the recommended weight.

90cc injectors dont put out much fuel in these trucks.

The newer trucks have bigger injectors and IC's.

I tow without an IC, I wish I had it sometimes, but it doesn't bother me much. I dont have issues with EGT's unless I'm driving stupid and lugging the motor to much.

 

Well that is good to know. In that case I'm guessing something is up with my pyrometer, or the stock tune from DP is not a true bone stock tune and a tune that is meant to run hot for emission testing.... Either way I can not make any more assumptions untill I get the new one in the manifold and see what is really happening. I might pull the chip out and drive it stock on the next trip and see what the temps do then, and compare it to the stock setting on the chip under the same conditions...

Any ways after reading Talyn's pyro thread I really hope I did not do any damage to the motor on this last trip, but I ran it on the coolest running tune and that happened to be the 140 agressive setting....

 

You have to run the EGT's around 1600 for extended period to damage the turbo.

A stock Tune from a programmer is going to run stock settings. I'm not sure if they adjust for fuel.

 

I thought running over 1250 is what causes premature ring wear and anything over 1400 starts fooling with piston melt down and head warping? These temps i posted in he first post were at the down pipe so I was guessing +300 at the header at certain points. Looking forward to seeing the true difference between the two..... All I could do was run it at the coolest setting and that was the max setting....sure burned through the diesel though


I want to say it again guys, but I really do appreciate all your help and info.... thank you!

 

WILLIAM

How hot do you figure the pistons will be by the time you see 1600* at the turbo?

 

I've seen many diesels running 1400* plus at the manifold for long periods of time. Granted it may shorten the overall life of the engine but have never seen it just melt down a piston under normal circumstances. Remember in these engines the pistons are being cooled by the oil spouts under them

 

So have I, I spent a little over 30 years driving them for a living. But there's a bit difference between 1400* at the manifold and 1600* at the turbo.

 

Cody has a post on the temp differences between the 2 points.


You'd have to run 1400 temps for a while for the piston to heat up that much when the engine is cooler.

I dont doubt it could damage the motor for extended periods of time.

But I also know there are guys on here, *cough*travis*cough* who abuse their trucks at the strip with High EGT's, or high EGT's from hauling and are not running into issues regarding those items.