WHAT GEARS DO I HAVE?
Le Mans Master
Joined: Jul 2002
Posts: 5,818
Likes: 2
From: Alive and well in Burlington NC
Re: WHAT GEARS DO I HAVE? (007rollie)
Mine runs ~1900 @ 70MPH and I have stock 2.59 gears. I would guess (a real SWAG) 3.07 for yours. You can check the RPO codes to see what it came with from the factory.
Advanced
Joined: Jun 2003
Posts: 63
Likes: 0
From: san antonio tx
Re: WHAT GEARS DO I HAVE? (007rollie)
I had 96 with Auto and 3.07. In OD mine was not that high in the RPM range. I would guess 3.45 or 3.73's. But that's just a guess. I think at about 70 mph mine was turning under 2000.
Safety Car
Joined: Sep 2003
Posts: 4,504
Likes: 0
From: Charleston SC
Re: WHAT GEARS DO I HAVE? (007rollie)
Rolling diameter of stock tires is about 24.8 in. Transmission ratios on the 700R4 and 4L60 are as follows: 1'st gear = 3.07, 2'nd gear = 1.63, 3'ed gear = 1, 4'th gear = 0.7 Use the following formula to find rear end ratios. (RPM*Tire Diameter)/(Trans ratio*MPH*336.16)
So:
007rollie (2500*24.8)/(.7*71*336.16)=3.71
Steel Blue 91 (1900*24.8)/(.7*70*336.16)=2.86
MrNuke (2350*24.8)/(.7*70*336.16)=3.53
bradvette (2450*24.8)/(.7*70*336.16)=3.69
Does this tell you something about the accuracy of our tacks? They all read a little high.
So:
007rollie (2500*24.8)/(.7*71*336.16)=3.71
Steel Blue 91 (1900*24.8)/(.7*70*336.16)=2.86
MrNuke (2350*24.8)/(.7*70*336.16)=3.53
bradvette (2450*24.8)/(.7*70*336.16)=3.69
Does this tell you something about the accuracy of our tacks? They all read a little high.
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Le Mans Master
Joined: Apr 2000
Posts: 6,341
Likes: 1
From: Shelton CT
Re: WHAT GEARS DO I HAVE? (rkessel)
Yea I dun trust my tach either. I'm getting a small analog tach just to see how much my stock LCD one is off by.
I knwo I have 3.45's though, so either the tach was off or I have smaller wheel/tire than stock. (I have aftermarket 17" and 275/40/17 tires)
I knwo I have 3.45's though, so either the tach was off or I have smaller wheel/tire than stock. (I have aftermarket 17" and 275/40/17 tires)
Instructor
Joined: Jan 2003
Posts: 233
Likes: 0
From: IL
Re: WHAT GEARS DO I HAVE? (6spd)
after lifting the rear wheels off the ground put it on jack stands. mark the drive shaft with a line, mark one of the wheels .slip the trans into neutral.turn the drive shaft counting the turns until the wheel makes one complete revolution this will give you the ratio.
Instructor
Joined: Mar 2003
Posts: 185
Likes: 0
From: West Sacramento CA
Re: WHAT GEARS DO I HAVE? (007rollie)
Under your center console you will have a decal with various codes. The code your looking for starts with a G. This is an RPO code. Here are the codes and what they equate to for the Dana 36:
Ratio= 2.59 RPO=GM1
Ratio= 2.73 RPO=GU2
Ratio= 3.07 RPO=G44
Ratio= 3.31 RPO=GW4
For the Dana 44:
Ratio= 3.07 RPO=G87
Ratio= 3.33 RPO=GT7
Ratio= 3.45 RPO=GM3
Ratio= 3.54 RPO=GHO
Hope this helps.
Ratio= 2.59 RPO=GM1
Ratio= 2.73 RPO=GU2
Ratio= 3.07 RPO=G44
Ratio= 3.31 RPO=GW4
For the Dana 44:
Ratio= 3.07 RPO=G87
Ratio= 3.33 RPO=GT7
Ratio= 3.45 RPO=GM3
Ratio= 3.54 RPO=GHO
Hope this helps.
