I've got a 4.6L and 4.0L D2 and just acquired a 4.0 GEMS D1 (96). The D1 seems to have "less" power than my 4.0L D2.

Is this everyone's experience ? Engine is very strong and I'm going through and doing all the maintenance and not finding any issues.

But it seems "slower" than my 4.0L D2.

thanks!

 

D2=Slipped cylinder sleeves
D1=slow pig that usually racks up over 200k if properly maintained.
(for the gasoline engines)

 

The D1 intake manifold is based on an early 80 sports car. The D2 intake manifold is designed in the late 90s for a truck.



From idle to about 3000RPM the D1 intake manifold is a terrible design.

 

That's what I suspected.... "just slow".. which I'm fine with. Quality of build seems so much better than D2 and parts are cheaper.

 

All my Bosch 4.0L’s are excellent. It’s the 03-04 4.6L’s that sucked!

 

 

My 98 LSE was actually not bad. It was slow off the line, but I cruised around 75-80MPH with no issues and I chirped the tires a few times. Throttle response and gear changes are just much better on the D2.

 

You can chirp the tires on the 5 speed D1 with normal sized tires

 

....when the sun gear in the transfer case grenades......