The hp on the 2valve should be 260 the 3 valve 300hp what is the hp for the 4 valve in the navigator? Is the 6 speed auto in the navigator new for 05?

 

4v has 300hp and the 6 speed is on the 05

 

'05 Nav also has the 3V 5.4 @ 300 hp. '04 was last year for 4V. Not sure about the advertised 6sp, but it is the torqueshift--other forums have mentioned the TS has 6 gears, but somehow only uses combos that = 5 speeds. I have looked at the shift selector on the Navs and seem like I remember 1-2-3-D, just like my '05 F350.

Anyone else know if it has six actual gear ratios?

 

Does anyone know why hte Navigator discontinued the 4V Intech motor?

 

Because the 3V motor has pretty much the same powerband, and it's cheaper to use the same engine (for the company, not necessarily the consumer) across the board. They don't have to worry about engineering concerns, they only have to smog certify 1 engine rather than 2, assembly line employees only need trained for one engine setup, less inventory for spare parts, etc. It's mostly to cut down on logistical concerns and requirements. Plus the new 3V has fewer moving parts, so (hopefully) they'll have less durability issues, and maintenance issues, equalling less warranty repair time paid out.

 

Actually, I believe the new 6 speed auto in the 05 Navi is made by ZF and is not a torqueshift. I thought I read somewhere that it is the same transmission they use in the new Range Rover and LR3. That would make sense since Ford owns Landrover. Anyone know better?

 

The 3V runs on regular as well. Even Lincoln owners don't mind saving a few million bucks a year at the gas pump.

 

Regular gas would be nice - what is the danger of using reg in the 4V....is there a knock sensor anyway?

 

When I bought my 03 the put reg and it was knocking.

 

I have a 99 Nav with the 5.4L 300HP 4v Intech. I have driven it since it was new (108k) and love this engine. Lots of power, very smooth. Recently I rented a 2005 Expy with the 3v 5.4L engine. It is supposed to be 300HP as well.
Peak HP is not all that matters, as torque is also important, especially in a truck. Where the HP and torque peak- and how wide that power band is- is also important. I haven't looked a chart for the power curve on these two engines, but I prefer my 4v over the 3v. This is after driving the Expy for about a month, and about 2000 miles.
What I found is the Expy seemed to have a lot of low end punch. This is probably an engine with more low end torque. It was quick off the line, which is nice for a big truck. On the other hand, my Nav does a much better job on the freeway at passing! The 3v engine just feels out of gas when you punch it at freeway speeds. It will get the job done, but you need to do a bit more advance planning.
I am not knocking this 3v engine, but it has made me seriously rethink replacing my truck with a new one. Thats a lot of dough for a Nav with an F150 motor!

As for running the 32v on regular gas- I have done it. The knock sensor kicks in constantly, and there is a loss of power and MPG. This is less true on 89 octane mid grade, but what it really wants is 91 or higher. I try to switch back and forth between 89 and 93, as 93 is more common here than 91, so I save a bit and keep the octane fairly in line. This requires more frequent fill ups to keep the blend about right.

 

What is your opinion on running ethonal?

 

I have used pump gas with 10% ethanol when i found it in Missouri. It didn't seem to cause any problems. It was also as cheap as the regular on sale at that station. I maybe run only one tank per year though, as I don't live there.
One thing about ethanol (which is a form of alcohol) is that it will remove any water from the fuel system by dispersing the water, allowing it to burn up with the gas.