1.4 Transfer Case into D1

[David Harris]

only found one and that was pick up only...

Yeah. Have to have someone get it for me and ship it, unless I can convince the seller to do it directly.

 

[muskyman]

Good post. I cant imagine why you would want to gear down to 1.4 in a stock vehicle when gearing down in the axles is more ubiquitous and thus, easier. If youre going to keep the gas motor, re gear the diffs.

Whatre you spinning at 65 mph again?

simple

the 3.54 gears are dirt cheap and everywhere.

on top of that they are the design ratio of the diff there for most likely the strongest ratio as far as holding up to shock load forces. A good example of this is the 3.73 ratio for a dana 60. According to dana if you move either direction from that ratio gear sets get weaker.

Some people that sell gears claim otherwise about rover gears but yet when asked over and over none ever seem to produce real numbers showing other ratio's are stronger. Rover clearly thought better of changing ratios as they elected to skin the cat with drive ratios in the transfercase.

For an enthusiast regearing the diffs is a much easier. Due to availability it is also likely a more cost effective way to accomplish the driving characteristics people are looking for.

 

[timmy!!!!!!!]

The other plus I have heard the 4.10 gears are make more noise than the 3.54.

 

[AxeAngel]

But eventually the diffs fail, if you have to go in and change them why not do gears and all at that time?

-Sam

 

[muskyman]

But eventually the diffs fail, if you have to go in and change them why not do gears and all at that time?

-Sam

99% of the guys doing a 1.4 or 1.6 have long since replaced the factory diffs with lockers or TT's so a broken diff really isnt a factor IMHO.

 

[David Harris]

Another plus is that since you're leaving the 3.54's intact, just replacing the carrier with a locker or TT is about a third of the work of doing the whole thing.

 

[R_Lefebvre]

Another thing to think about, if you do it with diff gears, you can lower your crawl ratio which is a good thing. It's way too high as it is. With the auto it was manageable because of the Torque Converter and left foot braking. With the manual, it's just way too high for really technical stuff.

 

[Viggen]

Another thing to think about, if you do it with diff gears, you can lower your crawl ratio which is a good thing. It's way too high as it is. With the auto it was manageable because of the Torque Converter and left foot braking. With the manual, it's just way too high for really technical stuff.

Good point. I would do the 3rd members before a transfer case. Lower gears in the axles give you better OVERALL reduction whereas, unless youre going to put an underdrive, youre not going to see any offroad benefits when in low whereas the gearset will give you the road gearing youre looking for AND a better ratio off road.

 

[David Harris]

Another thing to think about, if you do it with diff gears, you can lower your crawl ratio which is a good thing. It's way too high as it is. With the auto it was manageable because of the Torque Converter and left foot braking. With the manual, it's just way too high for really technical stuff.

LR's already have a way better crawl ratio than just about anything out there. The only better one I can think of stock is the Rubicon. After all most 4x4's have about a 2.6 or so low range, while the LR has a 3.3.

 

[R_Lefebvre]

Not true. The Land Rover crawl ratio is *exactly* the same as a NON-Rubicon JK. The Rover Low Range ratio is kind of lowish, but the axle ratio and 1st gear ratios hurt it. The Rubicon ratio is not just a bit lower, it's almost DOUBLE the ratio of the Rover.

I'm not going to go into a treatise about all the different ratios across all brands as I couldn't be bothered to look it all up. Suffice it to say, the Rover crawl ratio is not THAT low. It's better than an American full-size, but it's still not great.

 

[muskyman]

I'm not going to go into a treatise about all the different ratios across all brands as I couldn't be bothered to look it all up. Suffice it to say, the Rover crawl ratio is not THAT low. It's better than an American full-size, but it's still not great.

Your wrong on this...the effective ratio of a land rover is very low as far as 4x4's go through out history.

Yes the Rubicon has lower gears but it is the exception and also evidence that the off-road market has now caught on to the fact that lower gears are desired by consumers.

But to claim the low range crawl ratio of a land rover is "not great" you once again show you know very little about the history of 4x4's

 

[David Harris]

Not true. The Land Rover crawl ratio is *exactly* the same as a NON-Rubicon JK. The Rover Low Range ratio is kind of lowish, but the axle ratio and 1st gear ratios hurt it. The Rubicon ratio is not just a bit lower, it's almost DOUBLE the ratio of the Rover.

I'm not going to go into a treatise about all the different ratios across all brands as I couldn't be bothered to look it all up. Suffice it to say, the Rover crawl ratio is not THAT low. It's better than an American full-size, but it's still not great.

Here are the figures on crawl ratios:

LR Discovery
First Gear (Auto) 2.48
TC Low Range 3.32
Axle Ratio 3.54
Overall Crawl Ratio 29.14

Jeep JK Wrangler (Base)
First Gear (Auto) 2.84
TC Low Range 2.71
Axle Ratio 3.21
Overall Crawl Ratio 24.71

Jeep JK Rubicon
First Gear (Auto) 2.84
TC Low Range 4.00
Axle Ratio 4.10
Overall Crawl Ratio 46.58


As you can see, the Wrangler has a lower first gear, but the LR has a much lower transfer case low range and lower axle ratio in base trim, for an overall lower crawl ratio. Only the JK Rubicon can do better. Since JK's usually run taller tires than a LR stock, if you factor these in then the final crawl speed is even more in the LR's favor.

 

[R_Lefebvre]

I'm much more concerned with manual trans, as it's harder to go slow with a manual.

LR Disco:
3.32
3.32
3.54
39.0

Non-Rubi JK
4.46
2.72
3.21
38.9

Rubi JK
4.46
4.0
4.10
77

Hummer H3
3.75
4.03
4.56
68.9

Jeep TJ 4-banger
3.93
2.72
4.10
43.82

Jeep TJ I-6
3.83
2.72
4.10
42.71

Unimog U500

3000:1 :drool:

But to claim the low range crawl ratio of a land rover is "not great" you once again show you know very little about the history of 4x4's

I don't really care about what happened 20+ years ago. I'm talking about contemporary history here.

The problem with the LT230 is it doesn't have a 1:1 High Range. It's typically 1.2:1. The low range may appear to be low-ish at 3.3:1, but the fact is, it's really only 2.76 times the high range. This is important to keep in mind because most of us gear our trucks with overall drive ratio in mind. The LT230 1.2:1 high range ratio is why Land Rover can get away with a relatively steep 3.54:1 axle ratio. Most other trucks have a 1:1 high range, and maybe 4.11 axle gearing.

So the LT230 high-low range ratio is only 2.76. Let's go back 20 years and look at other transfer cases:

http://www.therangerstation.com/tech_library/TransferCases.html

Oh look. Most of them have a low range ratio of around 2.6-2.7. Funny that.

Making matters worse, the R380 does not have a granny-gear 1st. It's relatively high. 3.32:1. Something like the T-18 4 speed in a mid-80's Bronco had a 6.32 first gear. The NP435 transmission had a first gear ratio of 4.56 to 6.68.

I realize I'm attacking a sacred cow of the Land Rover community here but... these are just the facts.

 

[Antichrist]

I really liked the T18 granny first in the Travelall we had when I was a teenager. Even though it was only 2WD, with the 392 V8 it could idle up decent grades and along overgrown logging trails with ease.

 

[David Harris]

I'm much more concerned with manual trans, as it's harder to go slow with a manual.

True. With the manual it certainly evens out due to the rather low first gear of the manual Wrangler. But then again, the Wrangler is a six speed, to the Disco's five. The auto in a Disco gives you a better crawl ratio, in addition to the torque multiplication of the converter.