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Gear Ratios for:
All Land Rover manual gearboxes
Ashcroft high ratio transfer case
Every Land Rover nerd loves data. Especially if they are trying
to do something a little different with the drive train. I've
placed everything I could find about gearbox and Transfer case
gear ratios here in a hopefully readable way. If you are feeling
particularly nerdy you can also read my "history
of Rover gearboxes" web page.
Just for the fun of it I added the Borg Warner T-18 gearbox and
Ashcroft high ratio transfer case that is in The Green Rover for
comparison. Then I got requests to add other alternative gearboxes
available used in the North American market. Specs
for common alternative gearboxes have been placed on another
web page.
NOTE: Ratios are rounded off to the nearest hundredth.
Some ratios:
- Stock Series differential ratio - 4.7:1
- Stock coiler differential ratio - 3.54:1
- Common aftermarket differential ratios for the Rover differential
carrier - 4.1:1 and 4.75:1
- Standard Series transfer case high range ratio - 1.15:1 (making
it an under drive) . Low range varies
- Standard Coiler transfer case low range ratio - 3.32:1. The
high range varies with the engine used.
- Fairy/Superwinch overdrive ratio - 0.78:1
(which coupled with the 1.15:1 Xfer case under drive gives you
a 0.90:1 overall ratio through the xfer case)
- Roverdrive overdrive ratio - 0.8:1
(which coupled with the 1.15:1 Xfer case under drive gives you
a 0.92:1 overall ratio through the xfer case)
- Ashcroft high ratio kit high range ratio - 0.87:1
Some thoughts about low range first gear ratio:
I found the stock Series Land Rover low range first gear ratio
(40.7:1) to be too tall for most rock crawling and many climbing
situations.
Having over 5 years experience with a 70:1 ratio I have found it
to be too low for anything but the most technical rock crawling
situations (with 33.3 inch dia tyre). At this time I'm leaning
towards somewhere around 55:1 as being the best overall low range
ratio for use in many different situations with 32 - 34 inch dia
tyres.
Page Contents:
Series Gearbox Ratios: (Does
not include 109 Stage I V8 which uses LT95)
| Main gearbox |
Suffix A & B
88 & 109 |
Suffix C on
88 & 109 |
Ser. III
88 and 109 |
Ser. IIA & III
109 1-Ton |
Top |
Direct |
Direct |
Direct |
Direct |
Third |
1.37:1 |
1.50:1 |
1.50:1 |
1.50:1 |
Second |
2.04:1 |
2.22:1 |
2.22:1 |
2.22:1 |
First |
3.00:1 |
3.60:1 |
3.68:1 |
3.60:1 |
Reverse |
2.54:1 |
3.02:1 |
4.02:1 |
3.02:1 |
Early Coiler, 101 Forward Control and 109 Stage 1 V8 Gearboxes
| Main gearbox |
LT95*
109 Stage 1, 101, Range Rover thru '83
V8 90/110 '83 & '84 |
LT85
All V8 90/110
'84-'91 |
LT77/LT77S
2.5L & 200 Tdi
'84 thru '93 |
LT77/LT77S
V8 Discovery thru '93
V8 90/110 '92 & '93 |
Fifth |
none |
0.80:1 |
0.83:1 |
0.77:1 |
Fourth |
Direct |
Direct |
Direct |
Direct |
Third |
1.51:1 |
1.436:1 |
1.507:1 |
1.40:1 |
Second |
2.45:1 |
2.18:1 |
2.30:1 |
2.13:1 |
First |
4.07:1 |
3.65 |
3.59:1 |
3.32:1 |
*Note: The LT 95 has an integral transfer case. A
number of transfer case gears were available.
R380 Gearbox
| Main gearbox |
R380
All 300 Tdi Discovery & Defender
'94 to present |
R380
All V8 Discovery & Defender
'94 to present |
ZFHP22
Range Rover Classic
'92 - '03 Discovery, Defender V8
|
Fifth |
0.77:1 |
0.73:1 |
N/A |
Fourth |
Direct |
Direct |
0.728:1 |
Third |
1.30:1 |
1.39:1 |
Direct |
Second |
2.13:1 |
2.13:1 |
1.480:1 |
First |
3.39:1 |
3.32:1 |
2.480:1 |
GFT MT-82 Gearbox
| Main
gearbox |
GFT
MT-82
'07 Defender |
Transfer
case |
Sixth |
0.742:1 |
Hi range: 1.211:1 |
Fifth |
Direct |
Lo range: 3.269:1 |
Fourth |
1.223:1 |
|
Third |
1.721:1 |
|
Second |
2.839:1 |
|
First |
5.443:1 |
|
Note: Overall low range first gear is 57.1:1 and overall high
range sixth gear is 3.18:1
Series Transfer case Ratios:
| Transfer
case |
II, Suffix A &
B
88 and 109 |
IIA
suffix C on & III
88 and 109 |
109
1-Ton
IIA & III |
Ashcroft high ratio |
High transfer |
1.15:1 |
1.15:1 |
1.53:1 |
0.87:1 |
High transfer with 4.7 R&P |
5.4:1 ( 3686 RPM @ 65mph*) |
<- Same |
7.19:1 ( 4900 RPM @ 65mph*) |
4.01:1 ( 2737 RPM @ 65mph*) |
High transfer with 4.1 R&P |
4.7:1 ( 3208 RPM @ 65mph*) |
|
6.27:1 ( 4279 RPM @ 65mph*) |
3.57:1 ( 2437 RPM @ 65mph*) |
High transfer with 3.54 R&P |
4.07:1 ( 2788 RPM @ 65mph*) |
|
5.42:1 ( 3699 RPM @ 65mph*) |
3.08:1 ( 2102 RPM @ 65mph*) |
Low Transfer |
2.89:1 |
2.35:1 |
3.27:1 |
2.35:1 |
Low transfer with 4.7 R&P |
13.58:1 |
11.05:1 |
15.37:1 |
11.05:1 |
Low transfer with 4.1 R&P |
11.85:1 |
9.64:1 |
13.41:1 |
9.64:1 |
Low transfer with 3.54 R&P |
10.23:1 |
8.32:1 |
11.58:1 |
8.32:1 |
* Engine
RPM calculated with 4th gear (1:1) and 32 inch diameter tyres (stock
109 size) Calculator at csgnetwork
LT230 Transfer case Ratios
Transfer
case
LT230 |
Early Range Rover |
V8 D 110
300 Tdi |
V8 D90
Discovery |
2.5L Ninety, One Ten |
High transfer |
1.00:1 |
1.41:1 |
1.22:1 |
1.67:1 |
high transfer with
3.54 R&P |
3.54:1 ( 2416
RPM @ 65mph*) |
4.99:1 ( 3406
RPM @ 65mph*) |
4.32:1 ( 2948
RPM @ 65mph*) |
5.84:1 ( 3986
RPM @ 65mph*) |
high transfer with
4.1 R&P |
4.1:1 ( 2798 RPM
@ 65mph*) |
5.78:1 ( 3945
RPM @ 65mph*) |
5.00:1 ( 3414
RPM @ 65mph*) |
6.85:1 ( 4675
RPM @ 65mph*) |
high transfer with
4.7 R&P |
4.7:1 ( 3208 RPM
@ 65mph*) |
6.63:1 ( 4525
RPM @ 65mph*) |
5.73:1 ( 3911
RPM @ 65mph*) |
7.85:1 ( 5358
RPM @ 65mph*) |
Low Transfer |
3.32:1 |
3.32:1 |
3.32:1 |
3.32:1 |
low transfer with
3.54 R&P |
11.75 |
|
|
|
low transfer with
4.1 R&P |
13.62 |
|
|
|
low transfer with
4.7 R&P |
15.60:1 |
|
|
|
* Engine RPM calculated
with 4th gear (1:1) and 32 inch diameter tyres (stock 109 size)
LT95 Transfer ratio ( Integral part of LT95 gearbox)
LT95 gearbox
transfer part |
101 Forward Control |
110 |
90, Range Rover |
High transfer |
1.17:1 |
1.34:1 |
1.11:1 |
Low Transfer |
3.22:1 |
3.22:1 |
3.22:1 |
Overall gear ratio (final drive)
| gearbox position |
Series Suffix C &
newer |
109 1-Ton |
The Green Rover |
|
High transfer |
Low Transfer |
High Transfer |
Low Transfer |
High Transfer |
Low Transfer |
Top |
5.4:1 |
11.10:1 |
7.19:1 |
15.40:1 |
4.09:1 |
11.10:1 |
Third |
8.05:1 |
16.50:1 |
10.80:1 |
23.10:1 |
6.97:1 |
18.67:1 |
Second |
12.00:1 |
24.60:1 |
15.96:1 |
34.1:1 |
12.74:1 |
34.14:1 |
First |
19.88:1 |
40.70:1 |
26.46:1 |
56.56:1 |
26.06:1 |
69.83:1 |
Reverse |
21.66:1 |
44.30:1 |
28.91:1 |
61.78:1 |
|
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Engine RPM comparisons for Series gearbox with Roverdrive or
high ratio kit and for LT77S (same bellhousing bolt pattern)
Here is a comparison chart showing the differences for high range
fourth gear (1:1 ratio) RPMs at 65 MPH with 32 inch diameter
tyres mounted. Arranged in decending 4th gear RPM order.
vehicle & gearing |
Fourth gear RPM (32" tyres) |
Fifth gear or Roverdrive |
2.5L Ninety and One Ten |
3986 RPM @ 65 MPH |
3349 RPM @ 65 MPH |
Stock Series Land Rover |
3686 |
2951 |
V8 Defender with 4.1 ring and pinion |
3414 |
2628 |
tdi Ninety and One Ten |
3406 |
2827 |
Series Land Rover with 4.1:1 ring and pinion |
3208 |
2554 |
V8 Defender |
2948 |
2270 |
Series Land Rover with 3.54 ring and pinion |
2788 |
2223 |
Series Land Rover with Ashcroft high ratio kit |
2737 |
No fifth gear or overdrive |
ACKNOWLEDGMENTS:
This data came from several sources. It started with a 1971 Land
Rover technical document and mid eighties Rover Ninety and One
Ten dealer hand out brochure and grew through the help of many
people who volunteered additional data through e-mail. Particular
thanks to John Barge for his help in sorting out the coiler gear
ratios.
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