Engine/Transmission (1994 - 1998) What should EGT's be when towing???

[Archive]

Hi all, Perhaps some of you could give me an idea what I should expect in the realm of EGT's when towing.



My signature lists the truck, but the 4" exhaust is on it's way to me. A BD 4" from the turbo back.



Currently when pulling a 7500 lb trailer I get EGT's of 1100 on level ground , minimum head wind, at a speed of 60. Boost at about 8PSI

When I accelerate, I can easily hit 1300, but back off quickly.

When pulling a grade of say 2-3%. the Egt's climb quick and I constantly have to back off the throttle. Boost climbs to 25.



Power is not a problem - the EGT's are.



Will the 4" system lower the EGT's enough where I can pull a 9000lb trailer up a say 2-4% grade at say 55 to 60 MPH without having to worry about EGT's.



I understand all the basic factors involved, I. E. Tires, wind, humidity, ford alongside. . etc. . etc. .



Thanks guys, this is my first post, so be kind.

 

[Steve Campbell]

My opinion...

Have you had your timing checked? What kind of turbo mods do you have? Perhaps it is time to talk to one of the turbo gurus.

 

[Dave Remillard]

I'm unable to help with most of your questions, however I can give you a bit of comparison. When I had the #6 plate slide forward and the AFC forward, and pulling a 6,000lb. load up grades, I could not get the EGT's over 1150. My exhaust isn't the 4", but it is opened up some. Hope this helps a little.

 

[Koa Man]

The 4 inch exhaust will not have any advantage over the 3 inch, unless your stock exhaust is plugged (cat, muffler), then you will see a difference. Air mods will help a lot. A Scotty II would drop your EGTs by about 150*. PDR HX35/14 or 16 will drop it another 100-150*.

 

[SlyBones]

My opinion is the EGT's are too high for towing 7500 on flat level ground with min head wind. The 8psi part sounds about right, but not the 1100* part.



What are your temps and boost at 60 empty?



I didnt see what transmission youn have. But I assume this is an auto in OD. In this case I find the temps are higher and climb quicker when you are at low RPMs and ease into the throttle, versus when you are at higher RPMs and ease into the throttle.



Yes the 4" will help in lowering temps. Nuking the cat will make a big difference. For me this has been the single biggest EGT reduction piece. -- I did a catback, cat nuke, downpipe, turbo and megacannon each one piece at a time. My experience is the cat nuke is the single biggest EGT drop. However I did see improvements with these other items. The catback being the least improvement.



My experience is for level ground at 60 mph:

empty would 4 to 6psi and 500-700*

7000 load would be 8-10psi and 700-900*



As power is applied the boost and EGTs will rise much quicker,of course.



Towing 55mph up a 4% grade with EGT's in check. In my truck I would lock out the OD, and with my 3. 55 gears, would run 55 at 4% at 2250 or so RPMs. In this case I believe the temps would be fine. Less strain on things provides for less load and slightly less throttle position. I also have heard the added RPMs pump out the heat more efficiently. Less fuel, more efficient = less EGT.



If I left it in OD the RPMs would be down on the 1700 range or so. With the 7000 load, and 4% grade this would provide a good load on the engine and require more throttle to maintain speed. Less efficient at pumping out the heat, etc. I think the EGt's would be close here. Not to mention the added strain on the transmission.



If you have a manual, replace this with downshifting versus trying to leave it in 5th all the time.

 

[Boldt's Wagon]

Sure sounds like the cat is plugged.

 

[Got Smoke?]

Sounds like he needs an intake BOMB. Either a Scotty II or a AFE Mega Cannon.

 

[Eric_77]

Just did some towing and was checking EGT, boost, transmission temp as I have a new DTT transmission installed by James and this was first tow.



I am a little heavier than you ended up at about 3 times your trailer weight 20,790 pounds over the scales. (gross 27,440)

Trailer is 8ft by 8ft by 33 ft tandem axle single wheel enclosed van trailer. So I have a pretty good profile going down the road



Here are my numbers w/ 2-4 mph headwind

70mph actual speed (73 on speedo)

860-920 EGT

Boost 8-10 PSI

This is with stock exhaust w/ kitty

Diesel Dynamics fuel plate and boost elbow

Stock tire size (Michelin LTX )

 

[RHARVEY]

Flat ground with strong head wind. . around 800*. . See my sign. for details on the truck. Something that is not listed is the Wingmaster wing.



Rick

 

[Forrest]

Not sure which turbo, but it sounds way high. I agree ... the kitty needs roto-rootering. Oo.

 

[Deezul1]

The BHAF (big honkin air filter) dropped my EGT about 150deg and its around $40. 00. The 4" wont help much but a straight pipe will.

 

[gwizpro]

Thanks everyone, seems the culprit is probably the Cat. Talked with Mark @ TST and that is the first thing he said. Seems the cat on this truck is only good to around 70k miles.



Well, I will be punching thru the cat and installing a straight pipe thru it with the BD 4" exhaust and 5" tip. The cat thru pipe is just in case the inspector bangs on it. Need it to sound full ya know,,,



Will let you all know what happens next week. .



Thanks again all. .

The RackMan