We are looking to buy our first Excursion and really appreciate all the advice here on FTE. I've read about as much as I can find and I know a lot has been discussed on these topics, but would appreciate any specific advice you all may have for us. We are looking for a diesel EX to tow a 9,000lb TT and gear for a family of 7. We plan to spend a year on the road and I would guess the Ex would be hitched up about 50% of the time. We'll be out west at altitude for a large part of the year, which is one of the reasons we are focused on the diesels.

I am really torn between the 7.3 and 6.0. We've found some good trucks with both engines, and that would include only 6.0s that have had head studs and EGR work completed. But I can't decide whether the 7.3s with the 4R100 is really something to be concerned with. The problems with the 4R100 don't seem to be as talked about as those with a 6.0 engine. But when the problems are discussed, towing seems to be a significant contributing factor. We are looking at lower mileage trucks, between 90-140k mi, and if not already done, I would add the 6.0L tranny cooler to the 7.3. But other than changing the cooler and monitoring the temps, is there much else to be done to prolong the 4R100?

My goal is to get as reliable a setup as possible and avoid downtime on the road. I can fix most anything that comes up myself, but the less the better with the whole family in tow.

 

 

Uggh. This is exactly what I would wonder about. I can get receipts, vet the shop that did the work and all, but will never really know.

 

It’s not my daily driver, I have a work truck but on days off it’s my family vehicle and I tow my boat and tractor with it. It only left me stranded when the high pressure oil pump gave out last year. Other than that I’ve had no real big issues. I’m still driving it with a slight head gasket leak that’s pressurizing my coolant. I’ve put about $18k in it on parts alone but they were almost all upgrades and the parts they replaced were in fine working order other than the HPOP and a couple of small parts. It all comes down to how well it was maintained and with what parts. These trucks need clean fuel, clean oil and Motorcraft filters for the most part. You can’t run the **** out of them on oil that is way past it’s change interval and the cooling system must be properly maintained. What happens with them is one thing goes wrong and is not fixed properly, is misdiagnosed or ignored and it creates a domino effect that pretty much ruins the engine in a hurry.

 

And the head gasket failure is most likely not the truck, I installed a bigger turbo, bigger injectors, bigger air intake, bigger tires and left the engine the way it was thinking studs would hold. I should have put 4.11 gears, replaced the head gaskets and made sure the studs were correctly torqued and I’d probably have been fine.

 

Ah - that makes me feel better. Sounds like a sweet setup!

 

 

To answer your 4R100 question, flush the transmission to get ALL of the old ATF out and fresh new fluid in it, swap to the 6.0 cooler and watch the trans temp while towing. If it gets over 220* pull over and LET IT IDLE to cool off, NEVER shut off the engine with an overly hot trans. These things are the best bet to keep your 4R100 happy and healthy.
I bought my EX to serve as our TT tow rig too, but I chose a gas V-10 for a few reasons and have never regretted it once. Equipped with the factory optional 4.30 gears (or an equivalent taller tire and deeper gear combo) and a set of custom tunes to reprogram the trans shift strategy the V-10 can out tow a stock 7.3 rig. Yes, at higher altitudes the turbo motor will keep power output stable while the NA motor will drop some power, but that difference comes with a price tag.
We have logged over 37,000 towing miles (9,500 TH for 15K and the current 11,300lb TT for 27K+) and it has only needed a fuel pump replaced so far. It runs great, can hold OD on most Eastern Interstate Highway grades and sees 8 to 9.5 MPG dragging the 11K+ TT around on those highway trips.
Good luck on the EX purchase and the traveling adventure, I'm jealous!

 

My V10/4R100 Ex has 261,000 miles and is still towing a 10k camper with no issues. I don't know for sure that it's the original transmission but I've seen nothing to make me think it isn't. Our resident transmission guru, Mark Kovalsky, has stated numerous times that the 4R100 is reliable and completely capable of handling the torque from any STOCK engine that it was mated with. As long as you're not going to add a lot of power over stock, you should be fine. As Tom said, change the fluid and add a cooler. I've also owned a 7.3 powered F350 that had 330k on the clock when I sold it, and I never had a transmission issue with it.
As far as the engines go, you can't beat a 7.3 for reliability. They will not produce the power or fuel economy that the 6.0 will. In stock form, a 7.3 is downright boring to drive but, if you keep clean fuel and clean oil in it, it will bore you for hundreds of thousands of miles and never miss a beat. My 7.3 got around 15-16 mpg driving around and about 11-12 towing the 10k camper...that was in a 4x4 2001 F350 SRW with 3.73 gears.

 

Thanks, good things to think about. I think I'll lean towards a 7.3, and possibly a V10 if a nice one comes along.