What did They Change in '97?

[rebel_horseman]

Guys, what did FoMoCo / IH change back in '97? What's different between the '94-'97 7.3 and the '99-'03 7.3 engines?

Just wondering.

[><]

 

[Mike]

Fuel delivery and turbo and PCM. Not much else other than that. Higher volume HPOP and a waste gated turbine IIRC. There were sublte changes within the 94-97 year class as well. In 97 they started changing the fuel delivery system and injectors. Ford completely missed the boat on the 98 model year and as such there is no Heavy Duty 98 in existance. The Super Duty's rolled out in late 98 but were tagged as 99's, if you ever get to lift the hood of a 99 SD dont be surprised to see 97 components.

 

[rebel_horseman]

I always wondered what was different. You can hear the difference. The 94-97 trucks have more of a cackle, and an all around growl to them. The 99-03 trucks seem sto be slightly quiter and they should smoother. I've driven the old truck sand I swear they seem to have more power stock vs. stock than the 99's. i've always wondered why. Maybe they revamped the fuel curves and PCM and that caused it.

Thanks

 

[Duke]

A lot of experienced Ford 'Stroke owners think the '97 was the "peak" year for Ford diesels, but that could be simply an aversion to change we all go through when your favorite truck company changes body styles.

Aside from the motor changes, there are the obvious body style changes and the temporary drop to the Dana50 axle on the front end and the bigger Sterling 10.5" axle (from the Sterling 10.25" axle) in the rear end. Ford giveth, and Ford taketh away.

 

[whd507]

the 97s had split-fire injectors for the first time, some later ones had a smaller engine cover, no hood light, block heater might have been standard I dont remember, different wiring and some sensors were deleted during the 97 model year, when the small covered engines were installed. some of these things carried into the early 99s,

 

[dieselwiezil]

californian tree huggers ********!

 

[h2odrx]

the 97s had split-fire injectors for the first time, some later ones had a smaller engine cover, no hood light, block heater might have been standard I dont remember, different wiring and some sensors were deleted during the 97 model year, when the small covered engines were installed. some of these things carried into the early 99s,

Is this a fact?

 

[Russ]

No splits in my 97 and 99+ got intercoolers

 

[Mike]

No splits in my 97

Yeah, they were in the Cal models only in 97.

 

[h2odrx]

No splits in my 97

What is your build date?

 

[hheynow]

I believe the '97s have a check valve in the hpop to prevent drain back.

The '97s have different exterior molding than earlier years.

 

[tonkadoctor]

I believe the '97s have a check valve in the hpop to prevent drain back.

The '97s have different exterior molding than earlier years.

IIRC the leaking check valve was the reason for the HPOP resevoir drain back problems and the check valve was in the early PSD 94 - 95 or 96 and was converted to a standpipe in 96 or 97.

 

[Mike]

IIRC the leaking check valve was the reason for the HPOP resevoir drain back problems and the check valve was in the early PSD 94 - 95 or 96 and was converted to a standpipe in 96 or 97.

Correct, the 96-97's had a retooled front cover.

 

[h2odrx]

Yeah, they were in the Cal models only in 97.

Only Kali?

 

[hheynow]

IIRC the leaking check valve was the reason for the HPOP resevoir drain back problems and the check valve was in the early PSD 94 - 95 or 96 and was converted to a standpipe in 96 or 97.

That's what I meant.