RRMaximus said:

if you guys didn't have such thin skins you wouldn't have thrown out so many insults that I have been laughing at. And because I have been laughing at them I don't have a thin skin. Maybe logic is not your strong point.

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I doubt that we'd still be on here if we had thin skins.
I can vouch for many on here that they really don't!
My logic is pretty sound and you still haven't logically answered my last point!
This thread may now be moved to AG as it has gone more or less beyond the original concept and has got bogged down in personal issues.

Stanleysteamer said:

Well that'll teach me to post to you as I have done.
Those who know me well on here will admit that I often make mistakes and usually admit to them.
It could still be a crazy idea, fitting them may not be, but using them might be.
So you yourself still don't know the answer to your own question.

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Actually no, because every single person here who has given me a reason why the change would not work has given me reasons that are not valid. In fact the little data that they have presented shows that it would be reasonable.

So that part of my question has also been answered and I just didn't bother to mention that until now because it was so obvious to me and yet everyone seemed to think that they had proven the opposite.

I made it clear here some time ago that the only question I NOW needed answered was if they would fit. That was when I realized that the rest of my question had been answered.

And now that the question of them fitting has been answered through knowledge rather than experience I am satisfied fully.

I'm sure you will make up some story about how this isn't true but you can look through the comments and see the point where I make reference to just needing to know if they fit or not.

I also made it clear that given my use of the throttle I was happy that the engine would not labor with this change of differential.

And I also explained I had no concern that it would stay in fourth gear.

Also I mentioned how I can start in second gear to see the effect that it will have with the differential change on first gear operations.

Literally every concern that was raised, I have answered, meaning that my question has been fully answered.

You might not like those answers but this is not about you, this is about me.

So yes my question has been answered and your odds were wrong massively.

Hint this is the point where you realize that you are wrong and admit it.

RRMaximus said:

I have a 2002 4.4 Petrol L322 with front and rear diffs at the ratio 3.73, with the 5 speed ZF5HP gearbox.

My front and rear diffs are badly rusted on the outside but I do not believe that they need to be changed.

I plan to make a trip from England to Portugal and I was thinking to get two second hand diff that are in better condition, with the 2.76 ratio.

From looking at pictures of both types of diffs it seems that they have the exact same mounting points.

My reason for doing this would be to have a lower RPM when driving at 60 mph / 100 km/h on the trip.

Given that I could buy replacement diffs for around £100 each, I would most likely save the cost in reduced fuel consumption on the trip.

But my major concern is running the engine for a long time on a highway at a higher RPM than necessary.

I am not someone who needs or uses powerful acceleration, but I do prefer to run at a lower RPM on the highway.

If my current diffs were perfect then I would not consider this but as they are in bad shape on the outside it is something that I am considering.

I know that this would change the speedometer but I am not worried about that as I would use the GPS speedometer on my phone to mark the speed limits on my speedometer.

Please do not suggest that I sell my L322 and buy a supercharged version with the six speed gearbox because I have spent the past year fixing many issues on this car and I would not buy another car with unknown issues.

Is this a crazy idea or a good one?

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Best fuel economy is at max torque. Guessing on the petrol that's about 3000 rpm?

I'd leave it as it is. I'd also guess that given most fuel economy figures are quoted at 56 mph (80 kph) then that's probably what it has been tuned to do best at.

Is there a rubber doughnut on the rear prop? Not sure how that would take it if there is.

RRMaximus said:

I am sorry that I mentioned the fuel aspect, only to stop people saying that it was a waste of money. My main reason is to run the engine at a lower RPM on a long trip. Just to put a little bit less stress on a 23-year-old engine.

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Lower oil pressure too though and water pump will be spinning slower. It may actually be better to rev at 1300 rather than 1100?

Grrrrrr said:

Best fuel economy is at max torque. Guessing on the petrol that's about 3000 rpm?

I'd leave it as it is. I'd also guess that given most fuel economy figures are quoted at 56 mph (80 kph) then that's probably what it has been tuned to do best at.

Is there a rubber doughnut on the rear prop? Not sure how that would take it if there is.

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Yes but Grrrr remeber he doesn't care about fuel economy.

I do also wonder, if the diffs are that rusty, what are sills & arches like under all the plastic bits !!

Stanleysteamer said:

I doubt that we'd still be on here if we had thin skins.
I can vouch for many on here that they really don't!
My logic is pretty sound and you still haven't logically answered my last point!
This thread may now be moved to AG as it has gone more or less beyond the original concept and has got bogged down in personal issues.

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Actually the only reason that you kept arguing and insulting me is because of your thin skins.

If you had thick skins you would have shut up when you failed to prove a point.

Like I said, I have watched this forum for about a year, getting actual information from the very few people that give it.

I only came here because I had a question that could not be answered elsewhere.

So for a year I didn't come here because I have no interest in the ridiculous petty arrogance that I see on this forum.

Go back to my original comment where I say don't tell me to buy another car, and realize that this was in a response to seeing this petty attitude from others in the past.

Then read the patronizing comments that I basically ignored for hours until they became direct insults.

Then see that all I did was respond to the insults that had already been given to me.

Then you might understand why this whole experience has been funny, and why I have been ignoring this forum for a year, until I needed a question answered.

Unfortunately I didn't get an answer to my transfer case question, or solve my Gap tool problem, but I did get some helpful ideas.

pwood999 said:

Yes but Grrrr remeber he doesn't care about fuel economy.

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Yeah, just got to the bottom of the thread and see events have progressed.

Changing diffs is quite usual on race cars or where people change wheel sizes. Of course, those pursuits require a fair bit of fettling and expense anyway!

Guess we'll see how the experiment goes. The car can sit in traffic at 750 rpm with no issues and there's nothing to stop it dropping a gear if needs be so it'll probably be OK, just a bit slower off the mark.

pwood999 said:

I do also wonder, if the diffs are that rusty, what are sills & arches like under all the plastic bits !!

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Sills are fine, one arch is rusty and I'm fixing it this week. I just replaced all of the brake pipes and brake hoses on the car so I have been under it and in the wheel arches looking carefully at everything. There is also rust on the subframes and suspension that I was advised to do something about before the next MOT inspection.

RRMaximus said:

Actually no, because every single person here who has given me a reason why the change would not work has given me reasons that are not valid. In fact the little data that they have presented shows that it would be reasonable.

So that part of my question has also been answered and I just didn't bother to mention that until now because it was so obvious to me and yet everyone seemed to think that they had proven the opposite.

I made it clear here some time ago that the only question I NOW needed answered was if they would fit. That was when I realized that the rest of my question had been answered.

And now that the question of them fitting has been answered through knowledge rather than experience I am satisfied fully.

I'm sure you will make up some story about how this isn't true but you can look through the comments and see the point where I make reference to just needing to know if they fit or not.

I also made it clear that given my use of the throttle I was happy that the engine would not labor with this change of differential.

And I also explained I had no concern that it would stay in fourth gear.

Also I mentioned how I can start in second gear to see the effect that it will have with the differential change on first gear operations.

Literally every concern that was raised, I have answered, meaning that my question has been fully answered.

You might not like those answers but this is not about you, this is about me.

So yes my question has been answered and your odds were wrong massively.

Hint this is the point where you realize that you are wrong and admit it.

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You asked if it was crazy.
Until you have actually fitted them and driven them you still do not actually "know" the answer to your original question, and I don't remember throwing any insults at you either, maybe you could quote my insults.
The odds thing was about others on here, not you, knowing the answers, and only one person came on and said that they thought it should fit. Which I would say it extremely likely. But even he has not fitted it.

You really do get personal very quickly and in my case with the wrong person as I took you seriously for a lot longer than others on here.

You also happen to want to win every argument you get into, no matter what.
My ex was just like that, (as we were talking exes a while back). It cost her her marriage.

Also, re the "no one modifies cars"".
Well loads do, I for one seemingly never stop doing it, but then I did run a Kit car club and there is little more modded than that except perhaps Rods and Customs.

Grrrrrr said:

Yeah, just got to the bottom of the thread and see events have progressed.

Changing diffs is quite usual on race cars or where people change wheel sizes. Of course, those pursuits require a fair bit of fettling and expense anyway!

Guess we'll see how the experiment goes. The car can sit in traffic at 750 rpm with no issues and there's nothing to stop it dropping a gear if needs be so it'll probably be OK, just a bit slower off the mark.

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I am already slow off the mark, rarely using more than 1,500 RPM when accelerating so that is unimportant to me.

If I am on a steep hill needing to go forwards or backwards slowly I can put it into low range for that special rare situation.

But if I am doing a 6,000 mile round trip through Europe for a month having a 24% lower RPM on a 23 year-old engine that has not had proper servicing for many years will make me slightly more happy.

Stanleysteamer said:

Also, re the "no one modifies cars"".
Well loads do, I for one seemingly never stop doing it, but then I did run a Kit car club and there is little more modded than that except perhaps Rods and Customs.

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Exactly, someone told me that I could not do this modification because no one modifies cars anymore. That was their amazing insightful input. When I mentioned that people do modify cars they got offended.

Stanleysteamer said:

You asked if it was crazy.
Until you have actually fitted them and driven them you still do not actually "know" the answer to your original question, and I don't remember throwing any insults at you either, maybe you could quote my insults.
The odds thing was about others on here, not you, knowing the answers, and only one person came on and said that they thought it should fit. Which I would say it extremely likely. But even he has not fitted it.

You really do get personal very quickly and in my case with the wrong person as I took you seriously for a lot longer than others on here.

You also happen to want to win every argument you get into, no matter what.
My ex was just like that, (as we were talking exes a while back). It cost her her marriage.

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If you look at the passive aggressive comments that started from the moment I posted here, I didn't get personal for a very long time.

Comments like "you clearly know nothing at all about Mechanics" or something like that because I didn't agree with their stupid insulting comment.

It's just that I found it so funny that so many people with so little understanding wanted to act so intelligent.

That is what kept me here, the hilarious ridiculous comments, like put an LPG tank in your car to solve a problem that you do not care about, which does not solve the actual problem you care about.

I have been meaning to say this about the LPG comment, I'm guessing it's £2,000 to £3,000 for the installation. An L322 from 2002 is worth £3,000 for a good one. An L322 from 2002 with LPG is worth £3,000 for a good one. No difference in price. So I would spend more than what I paid for the car to install something that does not solve my problem that does not add any value to my car!

And I wouldn't have use of my car while the installation was being done!

If you don't find that funny then I don't know what is funny to you.

Grrrrrr said:

Best fuel economy is at max torque. Guessing on the petrol that's about 3000 rpm?

I'd leave it as it is. I'd also guess that given most fuel economy figures are quoted at 56 mph (80 kph) then that's probably what it has been tuned to do best at.

Is there a rubber doughnut on the rear prop? Not sure how that would take it if there is.

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Here is the torque curve for the engine.

I am not concerned with fuel economy.

I just want lower RPM on the highway.

Grrrrrr said:

Lower oil pressure too though and water pump will be spinning slower. It may actually be better to rev at 1300 rather than 1100?

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On that basis nobody should ever drive at 35 mph at the lower RPM? If the engine is cooled and has sufficient oil it doesn't matter. But higher RPM is more wear on the bearings, camshafts and cylinder bores.

Stanleysteamer said:

You asked if it was crazy.
Until you have actually fitted them and driven them you still do not actually "know" the answer to your original question, and I don't remember throwing any insults at you either, maybe you could quote my insults.
The odds thing was about others on here, not you, knowing the answers, and only one person came on and said that they thought it should fit. Which I would say it extremely likely. But even he has not fitted it.

You really do get personal very quickly and in my case with the wrong person as I took you seriously for a lot longer than others on here.

You also happen to want to win every argument you get into, no matter what.
My ex was just like that, (as we were talking exes a while back). It cost her her marriage.

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I don't think you were directly insulting but I think you did made insulting comments about me to others that I could see.

But there are a lot of people commenting here and I haven't really kept a track record of the level of rudeness of everybody.

I was more just looking at the fact that 90% of the people were happy to throw out abuse at me and make patronizing passive aggressive comments from the very start.

I have no interest in being right or wrong, because I know in the minds of everyone who insulted me here there is no way that I will ever be right, even when I am.

I came here with one purpose which was to find the answer to my question. I found an answer that, whilst not 100% guaranteed, was sufficient for my purposes. So I did get the answer that I was looking for.

But I got something much greater. I had planned to avoid the passive aggressive insults that I see regularly on this forum, but finding myself inside of the comments made me realize just how funny it could be.

So I got to enjoy a couple of days of laughing at people who believe that they are geniuses whilst making the dumbest comments.

If you watch the Jimmy Carr YouTube channel he makes funny jokes laughing at people who heckle him, who think that they are catching him out but they end up just looking dumb.

I did not plan this and I thought that I would want to avoid it but in the end I found it worth way more than the answer to my question.

Like the people who wanted to put odds that I would never get the answer to my question, posting directly after my post where I said that I had got the answer to my question.

To quote the late great Kevin Samuels, "You can't make this sh!t up!"

It has been a wild ride but now I have to get back to the rest of my life.

I hope you all enjoy being right about everything always even when you're wrong.

Oh I never mentioned this before but there is a thing called an overdrive gear that some people add to existing cars to help them drive better on the freeway.

I think that is available for the P38.

I think it's Ashcroft that do it.

But nobody ever modifies cars anymore...

You may well find you make your car go better and more economically simply by changing the exhaust.
I did that to my D1 300tdi, it certainly gave it more low down torque and the mpg was the same or better.
As I was going to do a lot of heavy high speed towing I also put HD springs on the rear, moved the rears to the front and replaced the shocks with GAZ ones to improve the body roll.
Overdrive is certainly the old skool way of doing what you would like to do, and I highly approve of it as I am basically an old skool sort of guy.
I would also change cams as that again is tried and tested. Going for a high torque cam in your case. Skimmed heads would come next.
I only have one Landy with a V8 in, which came replete with LPG. It runs very well indeed. It would probably be worth looking for one with lpg already fitted as, as you say, they come at no extra cost.

No, no one modifies car any more!

RRMaximus said:

I got divorced three years ago.

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After reading this thread I'm not surprised.

RRMaximus said:

I have an enormous amount of mechanical experience but I don't really care to justify it to you. I don't know anyone who doesn't understand that a lower RPM for many hours is better for the longevity of an engine.

I am not talking about an engine the way that Land Rover designed it. I am talking about my specific engine which you know nothing about but you seem to think you know best.

As for the rest, I have already stated many times that I do not need acceleration. And yet you mentioned it as a key component of your argument against my idea.

This is why I don't bother to listen to you, because you did not listen to me. I told you what I needed, and all you have done is tell me that I don't need what I need.

If acceleration is a problem I just put it into low range for those moments. Do you know that my car has a low range transfer case?

My car will comfortably rev over 5,000 rpm and yet when I drive it I almost never go over 1,500 rpm. So the amount of acceleration that I need compared to what is available is less than the 24% difference in the differentials.

Whatever the actual RPM would be, as I have stated before, the only thing that matters is they would be 24% less. Like someone driving around in third gear on the highway instead of using fifth gear. That would be dumb, since it would put more stress on the engine than necessary.

As for it not going into 5th, as I already explained to somebody else, I can just manually select 5th gear on the gearbox if it will not automatically upshift.

This is the problem that I have with you, everything you say has a simple solution and yet you don't seem to know that solution.

Anyway this is getting boring, you are just repeating the same things that you have said over and over again. None of them apply to my situation as I explained in the beginning.

But please do suggest I spend thousands on an LPG system and 1 inch bigger wheels and tires or buy a new car just to avoid spending £200 on alternative differentials. Then you will be one more of the many people who didn't read my question and proposed ridiculous answers.

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There is owt for nowt in this life. Gears as you obviously know are torque multipliers, witness how little strain is put on the engine in low range. Taller gearing will reduce the revs at any given speed but the trade off is that more torque is required so more strain on the drive line and more strain on your tired old engine as it has to work harder to produce the required torque.
So as far as I'm concerned, it matters not if the diesel diffs will fit your petrol car, you are labouring under a false premise.
Back in the 60's, cars would be revving their nuts off at 70mph so an aftermarket overdrive was a good idea to reduce revs from around 4K to 3K at 70mph, later gearboxes sprouted a tall 5th gear, either reduced NVH and made things calmer in the car. No idea if it improved fuel consumption as it only cost ten bob to fill up so we were not too bothered about economy.
These days an awful lot of development time goes into optimising the drive line for emission, economy and NVH so messing with the gearing is not such a good idea especially as it will have knock on effects with things like gear shifts. Low revs never did engines any good.
However, you are obviously a person who cannot accept anything that does not fit with your ideas.