Hey Mike!
You will notice that the engine is at a lower RPM at the same speed due to
the increased diameter of the tires. The wheels also weigh more. The
combination of these two things will account for a slower accelerating time.
If you pull anything, I would change out the gears. If you don't, let them
be and try it out. The 3.9L can handle it, I don't know about the automatic.
The automatic seams to shift just as you enter the torque range (around
3,500 has been my experience). This then takes your RPM's down to 2,500ish.
The 3.9L really needs to run in the torque to get up and go. I would get run
over trying to pull out in traffic here in the Detroit area (thankfully only
during working hours!). That was why I choose the manual so I could keep it
in the torque by shifting at 4,500 which takes me back to 3,500....still in
the torque.
I do not mean to start anything between the auto and man transmissions. The
traffic around me require that I can get out of the way while entering the
streets (mostly boulevards around here - divided streets with turnarounds
aka Michigan Left Turns ;) ).
Give the 3.92s a try and let us know what you think based on your needs.
Sean
'92 RC Sport 3.9L 5spd - 250,000mi!
'01 CC SLT+ 4.7L 5spd 3.92 LSD Mobil-1!
http://www.twistedbits.net/WWWProfile/dakota/DnuuSncssJujU
-----Original Message-----
From: Mike Pratt [mailto:pilot366@mediaone.net]
Sent: Monday, July 09, 2001 11:21 PM
To: dakota-truck@buffnet.net
Subject: DML: Gearing size question
I'm about to install 33x12.50 15 tires on my 99 Dak 4x4, the tires I am
running
right now are 31 inchers ,( from Factory), my truck is a 3.9L 6 Cyl.
Automatic, I am
also installing wider wheels ,( from 15x8 to 15x10).
My question is this; should I change the gearing to 4:10 or does it really
matter
and the gearing I now have will be fine. if I don't change gearing what
will
the consequence be.
This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 12:02:04 EDT