Changing gear ratios, is it worth it?
Thread Starter
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Three Wheeling
Joined: Jan 2019
Posts: 76
Likes: 6
Changing gear ratios, is it worth it?
hey guys, im considering swapping my ratios, from factory 3.54 to 4.11’s. I have 33” tires and a big rack (no pun intended). My truck absolutely sucks uphills. Anything paved with a grade, mountain passes, etc, forget about it. I feel like I’m going to blow a head gasket, and the truck hates life.
For ~$760 in parts, is it worth it? Does it make a noticeable difference?
A quick calculation gives the approx rpms of a stock d2 in 4th gear as:
2525rpms @ 70mph
2886rpms @ 80mph
For stock gearing and 33”s
2235rpms @ 70mph
2554rpms @ 80mph
For 4.11’s and 33”s
2602rpms @ 70mph
2974rpms @ 80mph
So currently I’m at about 290rpms less than what I should be at 70mph. The 4.11’s would be about 77rpms more than a factory rover at 70mph, so pretty close to factory.
Any thoughts? Obviously it’s not the flat freeway stuff I have problems with or short grade climbs <30min, but I can no longer take my truck up the longer mountain passes for fear of blowing the motor.
For ~$760 in parts, is it worth it? Does it make a noticeable difference?
A quick calculation gives the approx rpms of a stock d2 in 4th gear as:
2525rpms @ 70mph
2886rpms @ 80mph
For stock gearing and 33”s
2235rpms @ 70mph
2554rpms @ 80mph
For 4.11’s and 33”s
2602rpms @ 70mph
2974rpms @ 80mph
So currently I’m at about 290rpms less than what I should be at 70mph. The 4.11’s would be about 77rpms more than a factory rover at 70mph, so pretty close to factory.
Any thoughts? Obviously it’s not the flat freeway stuff I have problems with or short grade climbs <30min, but I can no longer take my truck up the longer mountain passes for fear of blowing the motor.
Last edited by Dsport; Feb 20, 2019 at 08:06 PM.
Three Wheeling
Joined: Jan 2019
Posts: 73
Likes: 5
hey guys, im considering swapping my ratios, from factory 3.54 to 4.11’s. I have 33” tires and a big rack (no pun intended). My truck absolutely sucks uphills. Anything paved with a grade, mountain passes, etc, forget about it. I feel like I’m going to blow a head gasket, and the truck hates life.
For ~$760 in parts, is it worth it? Does it make a noticeable difference?
A quick calculation gives the approx rpms of a stock d2 in 4th gear as:
2525rpms @ 70mph
2886rpms @ 80mph
For stock gearing and 33”s
2235rpms @ 70mph
2554rpms @ 80mph
For 4.11’s and 33”s
2602rpms @ 70mph
2974rpms @ 80mph
So currently I’m at about 290rpms less than what I should be at 70mph. The 4.11’s would be about 77rpms more than a factory rover at 70mph, so pretty close to factory.
Any thoughts? Obviously it’s not the flat freeway stuff I have problems with or short grade climbs <30min, but I can no longer take my truck up the longer mountain passes for fear of blowing the motor.
For ~$760 in parts, is it worth it? Does it make a noticeable difference?
A quick calculation gives the approx rpms of a stock d2 in 4th gear as:
2525rpms @ 70mph
2886rpms @ 80mph
For stock gearing and 33”s
2235rpms @ 70mph
2554rpms @ 80mph
For 4.11’s and 33”s
2602rpms @ 70mph
2974rpms @ 80mph
So currently I’m at about 290rpms less than what I should be at 70mph. The 4.11’s would be about 77rpms more than a factory rover at 70mph, so pretty close to factory.
Any thoughts? Obviously it’s not the flat freeway stuff I have problems with or short grade climbs <30min, but I can no longer take my truck up the longer mountain passes for fear of blowing the motor.
I am about to order up the ring and pinions for my own 200Tdi engined Discovery.
Camel Trophy
Joined: Oct 2016
Posts: 4,867
Likes: 1,410
From: Michigan
I'd say you are right there for a swap, 33's are the straw that breaks the camel's back, as far as I'm concerned. Missed a set of 4:11 gears with lockers last year, and kick myself every time I think about it.
Brian.
Brian.
Recovery Vehicle
Joined: Feb 2009
Posts: 1,198
Likes: 182
From: MEMPHIS, TN
From my experience with the 2 lr3 the stock one feels like a race car with stick tires compared to my lifted with rack and 32.5" tires. I would consider regearing if their was a option. I drove a regeared Disco on 35s and it felt really good still
Thread Starter
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Three Wheeling
Joined: Jan 2019
Posts: 76
Likes: 6
can you clarify? I think there are a couple typos in there. Are you talking disco 2 or LR3/disco 3?
4wd Low
Joined: Feb 2019
Posts: 13
Likes: 1
From: Archbold Ohio
Im not sure it would be any cheaper with the labor included.
But Ashcroft transmission has a ratio change on the transfer case for 275 pounds ($360).
That would change the overall gearing and instead of tearing apart 2 axles it would be one transfer case.
But Ashcroft transmission has a ratio change on the transfer case for 275 pounds ($360).
That would change the overall gearing and instead of tearing apart 2 axles it would be one transfer case.
Thread Starter
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Three Wheeling
Joined: Jan 2019
Posts: 76
Likes: 6
Isn’t this interesting? I’ve seen gear ratio changes recommended countless times in the “what tire size should I get” type threads. yet, not many who have actually gone through with it. I stack that up to most d1/d2/lr3/rr classic owners being thrifty do-it-yourselfer types. And an expensive parts change which requires speciality knowledge/tools, doesn’t really fit the demographic.