Stubbs
NAXJA Forum User
- Location
- Aztec, New Mexico
I have searched and thought, and thought and searched, and I cannot come to a conclusion.
I've got a 96 xj Country, 3.55 gears on a 4-speed auto tranny, Chryco 8.25 rear, Dana 30 front, with a recently installed 3" RC lift, 31x10.50's, and I'm pleased with the whole thing except for the gearing. My RPM's are far too low to produce substantial power, especially in the mountains, and especially towing. Towing in the mountains is atrocious.
I want to run 60 MPH at 2800-ish RPM's in 3 for towing, and I want to run about the same RPM's in overdrive at 75 not towing on the interstate. I find all kinds of gear ratio calculators on the net and , and I find mention of the XJ auto having a low overdrive around .69-.73, but I cannot seem to find ratios for the rest of the gears, especially 3rd.
If I "assume" 3rd is 1.0, and OD is .73, 4.56 gears seem to be where I want to be, but I'm about to place a lot of money on that assumption. All of the FAQ's say go with 4.10's on 31's, but my research has left me completely confused.
Can any of you steer me in the right direction?
TIA
Stubbs.
:wow:
I've got a 96 xj Country, 3.55 gears on a 4-speed auto tranny, Chryco 8.25 rear, Dana 30 front, with a recently installed 3" RC lift, 31x10.50's, and I'm pleased with the whole thing except for the gearing. My RPM's are far too low to produce substantial power, especially in the mountains, and especially towing. Towing in the mountains is atrocious.
I want to run 60 MPH at 2800-ish RPM's in 3 for towing, and I want to run about the same RPM's in overdrive at 75 not towing on the interstate. I find all kinds of gear ratio calculators on the net and , and I find mention of the XJ auto having a low overdrive around .69-.73, but I cannot seem to find ratios for the rest of the gears, especially 3rd.
If I "assume" 3rd is 1.0, and OD is .73, 4.56 gears seem to be where I want to be, but I'm about to place a lot of money on that assumption. All of the FAQ's say go with 4.10's on 31's, but my research has left me completely confused.
Can any of you steer me in the right direction?
TIA
Stubbs.
:wow: