Towing Multiple Issues

[SpyderXLT]

So, we took delivery of our 24' toyhauler last weekend, and decided to take it out for the first time this weekend. Ran into multiple towing issues! Help!?

The truck: '04 F-350, No mods except 285/75R16 Tires.
The load: 24' Toy Hauler, Approx 9,500 lbs.

The issues:

1) While towing, around 1800-2200 RPM, I'm experiencing what I believe is turbo surge. Sounds almost like the turbo is blowing off some pressure. Sounds like a cough or "whoosh" on the left side of the vehicle. Sometimes it only does it once or twice, and on occasion, it will do it repeatedly until I either accelerate or decelerate. Does this sound like turbo surge, and what's the best fix (other than avoiding that RPM range).

2) Fuel Economy! Okay, so PSDs are made for towing, but at 8.57 MPG (hand calculated)? The trip was about 115 miles one way, mostly gently sloped highway @ 60mph, the last 30 miles is windy, slow-going mountain roads. Elevation between 2025-3500 ft. Why such horrible mileage?

3) Experienced a extremely rich diesel smell in the cab when pulling uphill. The steeper the hill, the richer the smell. It can get to the point where it is almost sickening.Any ideas?

For all of the above problems, no check engine lights, or anything, and overall it towed fairly well. For towing a 9,500lb trailer, it seems like it has less power than I'd expect, but this is my first diesel. I'm planning on a 1200 mile (one way) trip at the end of summer and would like to have these issues cleared up before then. Any help would be greatly appreciated!

Thanks in advance!

-SpyderXLT

[StarDriver]

As far as your milage goes, that's about what I get pulling the big trailer, but if your bucking the wind and don't have a topper on your truck, that's about right for the milage.

[powerhoghp]

Diesel smell is probably a leaking up/down pipe to the turbo, this could cause lower mileage and also cause surging.

[Loubell]

The issues:

1) While towing, around 1800-2200 RPM, I'm experiencing what I believe is turbo surge. Sounds almost like the turbo is blowing off some pressure. Sounds like a cough or "whoosh" on the left side of the vehicle. Sometimes it only does it once or twice, and on occasion, it will do it repeatedly until I either accelerate or decelerate. Does this sound like turbo surge, and what's the best fix (other than avoiding that RPM range).

If this is the first time that your truck has pulled heavy weight in a long time, the turbo veins might be gunked up. It might go away , or it might need to be disassembled and cleaned. Could also be dirty EGR valve.

2) Fuel Economy! Okay, so PSDs are made for towing, but at 8.57 MPG (hand calculated)? The trip was about 115 miles one way, mostly gently sloped highway @ 60mph, the last 30 miles is windy, slow-going mountain roads. Elevation between 2025-3500 ft. Why such horrible mileage?
Is this MPG calculated round trip, or one way? Also, if you are pulling weight, up hill, on winding mountain roads, your milage will suffer, but also see below.

3) Experienced a extremely rich diesel smell in the cab when pulling uphill. The steeper the hill, the richer the smell. It can get to the point where it is almost sickening.Any ideas?

When I had this strong diesel smell, it was because the Y pipe before the turbo had cracked (fixed under warantee). The good news is that if it is pre turbo (the Y pipe) it will cause an underboost condition that will cause you to loose MPG. The bad news is that if you are out of warantee it is a pain in the neck to change out.

[SpyderXLT]

The smell turned out to be diesel exhaust in my coolant. BAM, head gaskets.

The turbo surge was alleviated by switching to Rotella T6 full synthetic. (Not sure why).

[howell_jd]

Ouch.

Thanks for re-visiting this thread to update everyone.

It does highlight the benefit of gauges to monitor engine performance since no codes were thrown.

While gauges won't identify failed headgaskets directly, the difference between oil and coolant temperature indicates oil cooler efficiency. The reduction of oil cooler efficiency is known to result in failed EGR coolers that provide a path to failed headgaskets through the production steam in the combustion chamber...tens of thousands of PSI will bend heads and stretch even ARP studs let alone stock TTY bolts.

Full synthetic oil is more shear stable and has a higher temperature flash point. You may have had some coking on the turboshaft from non-synthetic oil (turbo cool down importance...use of an EGT gauge supports this too). The replacement of non-syn with syn oil may have cleaned the coke deposits somewhat eliminating a sticky turboshaft. That and more use under high demand will also allow the variable geometry turbo vanes to operate over their full range of motion resulting in less surge too.

Glad you're back on the road and trucking!

Jonathan

[Galaxie]

Originally Posted by SpyderXLT

The smell turned out to be diesel exhaust in my coolant. BAM, head gaskets.

The turbo surge was alleviated by switching to Rotella T6 full synthetic. (Not sure why).

Glad you are on the road again and updates the thread. So you could actually smell the eg thu the coolant in the cab?!?!? Wow!


Sent from my iPhone using Autoguide

[robertc68]

Not to hijack but this thread may have helped me realize it could be headgaskets causing the diesel smell coming through my vents.I noticed it on my truck for a while but was thinking manifold or up pipe leaking,but this really makes me think headgaskets.