Runs like two different trucks

[jjohn]

Hi all
Have a long question about my 95, 3500, dually, with 69 K on it.
Modifications Performed: ( All parts from SS Diesel )
FSD Heat-Sync, Oil Pressure Sending Unit, Lift Pump, Triple gauge package w/pod, Cooling upgrade kit, Cooling Fan upgrade, Wastegate solenoid valve, # 9 Resistor, and a 4" Exhaust System, not from SS, came with truck.
Recent Work Performed:
Replaced signal lite unit, Replace radio as it quit, replaced stop lite switch, new glow plugs, replaced head lite switch two times, Accelerator pedal position sensor Module as per local dealer. ( Codes 84 & 99 )

Now the Problem????

I tow a 21 foot horse trailer, about 8900 LBS. With no trailer I get 15.4 mpg. At 60 mph it turns 2200 rpm with 2 lbs boost, and 500 deg. egt, and 200 deg. tranny tem. The tire size is LT.225/75R16 115/112 Q 10 PR.
With the trailer I get between 9.4 and 11.6 mpg. On my last trip of 2566.7 miles to Tx and back ( Buffalo ) I avg. 10.7290 mpg. I know this looks good, but when I am getting the 9 mpg, I have to watch my egt, as I have to work to keep it below 1000 deg. and the truck does not seem to have the power it should. How ever when I am getting the 11+ mpg the truck runs great, with lots of power, and I even get to pass other cars. And the egt stays between 600 and 900 deg.except on long hills.
This truck was in storage for a couple of years or so, and it apears to have had wiring problems, as some of the wiring harness has been taped, and or redone. Because of this and the parts I have had to replace, I am thinking maybe the ECM has problems.

Thanks for any help you may have
JOHN

[TedReminder]

You didn't say anything about getting more fresh air in the engine. The 4" pipe will let it out nicely. The #9 resistor is putting a bit more fuel in the mix. Extra fuel, the way I understand it, is just extra fuel till it has extra air to get it burned. Extra fuel might contribute to high EGT in your case.
Ted

[jjohn]

Hi,
Sorry, yes I do have a SS Diesel air induction kit on it. Also I have never seen the boost pressure above 6 psi,

JOHN

[DragNasty]

No trying to hijack you thread but my 99 is similar. I run no boost at all running 75mph at around 600 egt. Is that normal? My boost spikes at about 11psi when taking off under heavy acceleration but other that that, never goes over 6 psi. This is all when NOT pulling a trailer. I had my egt get up to 1100 a couple times momentarly when pulling hills. Is that bad?

[stumppuller]

at 60 miles an hour average boost is 2-3 pounds,i believe 6.5 pistons melt at 1150 deg.get those temps down i run 400deg at 60 mile an hour 0-2 pounds boost.

[jjohn]

Hi
But what do I do to get the EGT tem. down ?

John

[RckyMtNDeZL]

I thought the cooling upgrades you have in place would solve any overheating problems. I notice you run 225/75/r16 on your rig. Is that the O.E. size? Just curious, you need a EE load rated tire if my memory serves me, or dual ply. That is alot of weight, and those tires are important for putting them horses on the pavement. Water wetter works to stabilze temps as well. Maybe time for a flush and fill?

[DragNasty]

I thought the cooling upgrades you have in place would solve any overheating problems. I notice you run 225/75/r16 on your rig. Is that the O.E. size? Just curious, you need a EE load rated tire if my memory serves me, or dual ply. That is alot of weight, and those tires are important for putting them horses on the pavement. Water wetter works to stabilze temps as well. Maybe time for a flush and fill?


The coolent doesnt cool down the exhaust temps. Some of the duallys came factory with 225/75/16 size tires. They are E rated. I use to have them on my old dually.

[snoddytn]

I was wondering if there was a gasket between the upper intake where you tap the manifold and the bottom part that you don't pull off the engine to tap

[TedReminder]

I was wondering if there was a gasket between the upper intake where you tap the manifold and the bottom part that you don't pull off the engine to tap

Yes there is a gasket.
Ted

[962500]

have you tried replacing your turbo wastegate solenoid. mine didnt show a code but i wasnt getting very good power so i changed it (only 30$) takes about 5 minutes and its like a new truck again.