My crazy diff ratio change idea

[RRMaximus]

@RRMaximus you have alot of perseverance.

You keep on bleating that you want to lower your RPM but if not fuel economy then why?
If its for engine longevity you do realise that a lower RPM but higher throttle request cause higher cylinder preasures. Higher cylinder preassures cause, more bearing wear, more cylinder bore wear, more piston ring wear, higher combustion temps, more valve seat wear, this list can probably go on for quite a while.

I think you are imagining an extreme situation and not looking at this in reality.

For example, someone else said that the oil pressure would be lower and that would damage the engine.

But I can drive now at 40mph at the same approximate revs as I will have at 50mph with the changed diffs and my engine has plenty of oil pressure at those RPM.

It might be 5% less oil pressure than normal which will be way inside what is required.

I think that you people are imagining things at an extreme to make an irrelevant point.

How much higher cylinder pressure would there be?

Do you have a way to calculate that?

How much extra wear would there be?

Lugging might happen if I was driving at 20mph in 5th gear, with the throttle wide open, but that will not be happening.

Given the low down torque of my engine, and the VANOS system, driving at 1,500 versus 1,900 at 70mph will not cause lugging.

The 6 speed L322 will do about 1,900 RPM at 70mph and the 8 speed L322 will do about 1,400 RPM at 70mph.

Why would Range Rover lower that RPM if there are so many issues with doing that?

Your comment only makes sense if I was loading up my car with a heavy trailer, but I am running it very light, as mentioned already.

Therefore the engine will be operating at the least weight end of the scale that it has been designed to run at, and it will easily handle the load of that weight at a lower RPM.

All of this has been explained by me already.

If I was driving a high revving 4 cylinder engine with a huge load at a low RPM in a high gear with the throttle fully open then I could accept your comment.

That is not the case at all, as my engine has a lot of low down torque.

This is just like someone who changes up gears early in a manual car because they do not need to squeeze that last bit of acceleration out of the car.

In normal operations this puts less stress on the engine.

Likewise, holding a car in lower gears longer than needed puts more stress on an engine.

In an extreme example there could be issues, but they typically come when the throttle is wide open, which is nowhere near where I will be in my modified L322.

As someone said on another forum, they knew someone who did something similar and they had no issues, just a reduction in their acceleration, which I do not care about.

 

[RRMaximus]

For the benefit of all future readers it might be good if you shared the detail of that. It might make you come out of this thread less negatively

I have no concern for how I seem here.

I asked a simple question and I was insulted and attacked from the start.

Those people will never change their opinion of me, especially after I called them out on their ridiculous behavior.

I will not post another question here again, because it is 99% garbage for 1% value.

The juice is not worth the squeeze.

I only remain here because it is funny to see those people desperate to prove me wrong, long after I have already got my answer.

But now it feels like the comedy value is diminishing versus the time that I have to invest in keeping the conversation going.

Eventually the outrage at my simple idea will die down, and I will be forgotten, happily.

I look forward to the day when no one new or old feels the need to comment here again.

I only see the comments because I am checking in on another thread where I got some very good advice on another issue.

 

[Mark Piercy]

I have no concern for how I seem here.

I asked a simple question and I was insulted and attacked from the start.

Those people will never change their opinion of me, especially after I called them out on their ridiculous behavior.

I will not post another question here again, because it is 99% garbage for 1% value.

The juice is not worth the squeeze.

I only remain here because it is funny to see those people desperate to prove me wrong, long after I have already got my answer.

But now it feels like the comedy value is diminishing versus the time that I have to invest in keeping the conversation going.

Eventually the outrage at my simple idea will die down, and I will be forgotten, happily.

I look forward to the day when no one new or old feels the need to comment here again.

I only see the comments because I am checking in on another thread where I got some very good advice on another issue.

 

[RRMaximus]

Here is the funny thing, the biggest actual potential problem that I have so far been alerted to is the torque converter lockup.

Here is what the ZF5HP guru RRPhil said on another forum: "Some aspects of the driveline control are vehicle speed related e.g. the torque converter lock-up clutch currently locks at 56mph... so I don’t know if those speed signals come from upstream or downstream of the final drive and therefore how they would be affected."

Do you see what he did there?

He pointed out a potential problem and then immediately said that he did not know if it would affect the operation or not.

Phil did not say: "You are going to cause the torque converter to not lock up and you will destroy it, are you crazy?!"

No hysteria, no exaggeration of information into a catastrophe, just the facts that he knew and the facts that he did not know.

The simple solution to this is that if I do the differential swap then I would use my OBD reader to make sure that the torque converter has locked up on the highway.

So the obvious next step is for me to plug in my OBD reader, select the gearbox control module and see if the torque converter lockup is one of the parameters that my OBD reader can see on my car.

If my OBD reader does not see this parameter then it would be costly for me to proceed, as I would have to buy a more advanced OBD reader which would probably be the gap iid tool at around £500.

The torque converter not locking up would be a major problem, compared to insignificant problems that people here have tried to turn into major problems.

This is a simple non hysterical factual approach to assessing the validity of doing this particular alteration to my car.

Here is what someone could have said to me, "The torque converter might not lock up, so you should have an OBD reader that can see if that happens or not, and test the situation as soon as you make the modification."

That would be a non-patronizing, non-arrogant, non-attacking, factual based piece of advice directly relevant to my question.

I have tried to find out the answer online as to what inputs determine when ZF5 HP torque converter lockup happens, but so far I have not been able to find this information.

Perhaps someone out there knows the answer to that question.

 

[Datatek]

Here is the funny thing, the biggest actual potential problem that I have so far been alerted to is the torque converter lockup.

Here is what the ZF5HP guru RRPhil said on another forum: "Some aspects of the driveline control are vehicle speed related e.g. the torque converter lock-up clutch currently locks at 56mph... so I don’t know if those speed signals come from upstream or downstream of the final drive and therefore how they would be affected."

Do you see what he did there?

He pointed out a potential problem and then immediately said that he did not know if it would affect the operation or not.

Phil did not say: "You are going to cause the torque converter to not lock up and you will destroy it, are you crazy?!"

No hysteria, no exaggeration of information into a catastrophe, just the facts that he knew and the facts that he did not know.

The simple solution to this is that if I do the differential swap then I would use my OBD reader to make sure that the torque converter has locked up on the highway.

So the obvious next step is for me to plug in my OBD reader, select the gearbox control module and see if the torque converter lockup is one of the parameters that my OBD reader can see on my car.

If my OBD reader does not see this parameter then it would be costly for me to proceed, as I would have to buy a more advanced OBD reader which would probably be the gap iid tool at around £500.

The torque converter not locking up would be a major problem, compared to insignificant problems that people here have tried to turn into major problems.

This is a simple non hysterical factual approach to assessing the validity of doing this particular alteration to my car.

Here is what someone could have said to me, "The torque converter might not lock up, so you should have an OBD reader that can see if that happens or not, and test the situation as soon as you make the modification."

That would be a non-patronizing, non-arrogant, non-attacking, factual based piece of advice directly relevant to my question.

I have tried to find out the answer online as to what inputs determine when ZF5 HP torque converter lockup happens, but so far I have not been able to find this information.

Perhaps someone out there knows the answer to that question.

On the P38, torque convertor lock up is not wheel speed related as far as I can determine but engine revs related. Lock up in third happens at about the same revs as lock up in top but at lower road speed of course and depends on throttle opening. The L322 being much more complicated with a variable slip lock up clutch so may use more parameters for lock up. Another potential problem for you to advise us about along with the likelihood that it will not pull top gear unless you have the wind behind you. I also wonder if a fault may be logged as the wheel speed will not match the output shaft speed that the electronics expect. Lots of interesting things for you to tell us about.

 

[Propman]

Perhaps someone out there knows the answer to that question.

In response to your request for answers, may I present you with exhibit A.

I'm not going to waste time answering your questions when you can look it up yourself if it actually matters to you.

 

[Mark Piercy]

Here is the funny thing, the biggest actual potential problem that I have so far been alerted to is the torque converter lockup.

Here is what the ZF5HP guru RRPhil said on another forum: "Some aspects of the driveline control are vehicle speed related e.g. the torque converter lock-up clutch currently locks at 56mph... so I don’t know if those speed signals come from upstream or downstream of the final drive and therefore how they would be affected."

Do you see what he did there?

He pointed out a potential problem and then immediately said that he did not know if it would affect the operation or not.

Phil did not say: "You are going to cause the torque converter to not lock up and you will destroy it, are you crazy?!"

No hysteria, no exaggeration of information into a catastrophe, just the facts that he knew and the facts that he did not know.

The simple solution to this is that if I do the differential swap then I would use my OBD reader to make sure that the torque converter has locked up on the highway.

So the obvious next step is for me to plug in my OBD reader, select the gearbox control module and see if the torque converter lockup is one of the parameters that my OBD reader can see on my car.

If my OBD reader does not see this parameter then it would be costly for me to proceed, as I would have to buy a more advanced OBD reader which would probably be the gap iid tool at around £500.

The torque converter not locking up would be a major problem, compared to insignificant problems that people here have tried to turn into major problems.

This is a simple non hysterical factual approach to assessing the validity of doing this particular alteration to my car.

Here is what someone could have said to me, "The torque converter might not lock up, so you should have an OBD reader that can see if that happens or not, and test the situation as soon as you make the modification."

That would be a non-patronizing, non-arrogant, non-attacking, factual based piece of advice directly relevant to my question.

I have tried to find out the answer online as to what inputs determine when ZF5 HP torque converter lockup happens, but so far I have not been able to find this information.

Perhaps someone out there knows the answer to that question.

 

[RRMaximus]

On the P38, torque convertor lock up is not wheel speed related as far as I can determine but engine revs related. Lock up in third happens at about the same revs as lock up in top but at lower road speed of course and depends on throttle opening. The L322 being much more complicated with a variable slip lock up clutch so may use more parameters for lock up. Another potential problem for you to advise us about along with the likelihood that it will not pull top gear unless you have the wind behind you. I also wonder if a fault may be logged as the wheel speed will not match the output shaft speed that the electronics expect. Lots of interesting things for you to tell us about.

Now we are getting somewhere. Real issues without the "I know everything" attitude.

The lockup occurs at around 50 mph and will obviously be affected by RPM and throttle.

But a car with a trailer will have the same RPM but a higher throttle position than a car without a trailer, and this does not stop the torque converter lockup clutch working.

Therefore I cannot imagine that my set up would instantly disable the lock up clutch.

Given that I will probably be driving at 70 mph or 80 mph this is a significantly higher speed than 50 mph so likely there will be enough inputs for the lockup to occur.

But as I said, my OBD reader should be able to answer that question instantly.

As for not pushing fifth gear, it will currently drive in fifth gear at low RPM without any problem, so I don't see that happening.

But the L322 has a manual selection on the gearbox so I can put it into fifth gear as I start on the next section of Spanish motorway.

I have no problem with a fault being logged if it does not affect the engine or gearbox.

The issue would be if the (ABS measured) wheel speed, RPM and gear selection threw up an error that caused the car to go into a failsafe mode and not drive properly.

Some people put on oversize wheels for off-road driving on these cars and I have not seen any mention online of this action shutting down the car.

Also when off-road driving one wheel could be off the ground and spin rapidly under power and I have not seen any comments about this situation shutting down the car.

So while your comments are valid, if I look through each one, think about them, and look at the available information I can find online, none of them seem to be actual problems.

 

[RRMaximus]

In response to your request for answers, may I present you with exhibit A.

Actually the person asked me a question that would take 10 seconds to find on Google and I suggested that they look it up because it was a question unrelated to my question.

They wanted to know all of the gear ratios for the L322, and they also questioned whether the 2.76 ratio even existed, and wanted to know which specific car it came from.

So their question was part of the general condescending patronizing view that I can't possibly know anything.

It suggested that I wanted to put a differential on my car that did not even exist.

In the end I did take a screenshot of a Google search and also sent them a picture of the exact differential on sale that mentioned the ratio and what car it came from.

So I did answer their question.

Now tell me what is your favorite color, what exact car do you drive, where do you park it, how long have you had it for, how many miles exactly has it done, how many people are on the insurance and who did you vote for in the last general election?

All of these questions relate directly to my issue about the differentials and I will need you to answer them before I can proceed.

And if you don't answer all of the questions then there is something wrong with you, not something wrong with me for asking these ridiculous irrelevant questions.

Now do you understand, or do you want to try another pathetic gotcha attack and fail again?

And best of all, I just explained that I did try to look up the answer to this question about the input factors that determine the torque converter lockup and I cannot find it.

Therefore telling me to look it up would be ignoring what I just said and saying something really dumb.

Whereas in the case of the other guy, it literally comes up in 10 seconds on Google and therefore telling him to look it up was a logical thing to do.

But feel free to prove once more that you are a nasty idiot with another gotcha comment.

 

[Propman]

Actually the person asked me a question that would take 10 seconds to find on Google and I suggested that they look it up because it was a question unrelated to my question.

They wanted to know all of the gear ratios for the L322, and they also questioned whether the 2.76 ratio even existed, and wanted to know which specific car it came from.

So their question was part of the general condescending patronizing view that I can't possibly know anything.

It suggested that I wanted to put a differential on my car that did not even exist.

In the end I did take a screenshot of a Google search and also sent them a picture of the exact differential on sale that mentioned the ratio and what car it came from.

So I did answer their question.

Now tell me what is your favorite color, what exact car do you drive, where do you park it, how long have you had it for, how many miles exactly has it done, how many people are on the insurance and who did you vote for in the last general election?

All of these questions relate directly to my issue about the differentials and I will need you to answer them before I can proceed.

And if you don't answer all of the questions then there is something wrong with you, not something wrong with me for asking these ridiculous irrelevant questions.

Now do you understand, or do you want to try another pathetic gotcha attack and fail again?

Nah, I’ll just remain rent free in your head. Whilst you clearly survive on pay per word.

You have a good day now.

 

[marjon]

Actually the person asked me a question that would take 10 seconds to find on Google and I suggested that they look it up because it was a question unrelated to my question.

They wanted to know all of the gear ratios for the L322, and they also questioned whether the 2.76 ratio even existed, and wanted to know which specific car it came from.

So their question was part of the general condescending patronizing view that I can't possibly know anything.

It suggested that I wanted to put a differential on my car that did not even exist.

In the end I did take a screenshot of a Google search and also sent them a picture of the exact differential on sale that mentioned the ratio and what car it came from.

So I did answer their question.

Now tell me what is your favorite color, what exact car do you drive, where do you park it, how long have you had it for, how many miles exactly has it done, how many people are on the insurance and who did you vote for in the last general election?

All of these questions relate directly to my issue about the differentials and I will need you to answer them before I can proceed.

And if you don't answer all of the questions then there is something wrong with you, not something wrong with me for asking these ridiculous irrelevant questions.

Now do you understand, or do you want to try another pathetic gotcha attack and fail again?

And actually that person will now attach some docs he has searched for to help some insight into these questions (yet again).

In his next post .

J

 

[RRMaximus]

Nah, I’ll just remain rent free in your head. Whilst you clearly survive on pay per word.

You have a good day now.

Oh you don't remain rent-free in my head, as all of you idiots are just a big blur to me.

One of you said something to imply that I actually remember who says what.

I just look at the comment, see how dumb it is, and then respond, while laughing.

One of you posted a comment here telling everyone to stop interacting with me and then they kept interacting with me themselves.

I don't remember who it is because I don't care but it might've been you.

Whoever it was it's really funny, because it seems like you are the guys who just can't stop with these endless pathetic loser attacks even when you tell yourselves to stop.

I use voice dictation to write these comments whilst doing something else at the same time so I'm not investing much time into this.

But I do get to laugh about you guys for a lot longer than I spend commenting here, so the value for time input is actually pretty good.

 

[RRMaximus]

And actually that person will now attach some docs he has searched for to help some insight into these questions (yet again).

In his next post .

J

If any of you has just started with the presumption that I wasn't an idiot then this whole discussion would've gone a completely different way.

My comments are in response to how I was treated and that is a reflection of the people here, not me.

As I have said many times now, I have seen other people being treated the same way here and just leave, which is why I have avoided commenting here for almost a year.

 

[Propman]

Oh you don't remain rent-free in my head

Oh but I do.

 

[RRMaximus]

Oh but I do.

No you don't, because I only comment here when I see the little red alert and then I read the next idiot comment.

You personally don't live rent free in my head because I don't even know who you are.

But given that you have continued to come back here again and again and again and again and again and again and again for no purpose other than to insult me, it's clear that I live rent free in your head.

Remember, I came here to answer a question about my car, so I have a reason to read new comments here that might give me more or new information that might help me.

Why are you still here?

Clearly something is bothering you and you cannot just move on, even though you have no legitimate reason to be here.

 

[pwood999]

Did you rebuild the gearbox yet, or just assume it was low fluid ??

 

[RRMaximus]

Did you rebuild the gearbox yet, or just assume it was low fluid ??

Another gotcha question!!!

You guys are ridiculous.

What does that have to do with the topic that I came here to answer?

Let me teach you a little trick, when you drain your gearbox in order to change the filter you see how much fluid comes out of it.

And if you go onto another thread on this forum you can see the post by SaintV8 about how to do this filter change, and you can see how much fluid should come out of it.

My gearbox should have had at least 4 L come out of it, and it only had 1 L.

This was after I was having some gear change problems, and I was given advice by RRPhil on how to troubleshoot them.

There was no need to rebuild the gearbox to determine that it was low on fluid.

Only an idiot would think that.

But hey let's assume that I just guess things like the fluid level of my gearbox and don't actually check.

Let's assume that I'm the idiot, because otherwise that would make you the idiot.

Actually my car had a twisted gearbox sump and a fluid leak which caused the low fluid situation and I fixed that issue as well.

I also replaced the fluid twice because you cannot get all of it out and by doing it twice you mix it with the old fluid and get a higher overall ratio of new fluid to old fluid.

All of this information about how to do this is available on the forums from people who post actual information rather than attack people.

But this has nothing to do with my question here, so I guess you just wanted to try another gotcha comment, and failed.

 

[marjon]

If any of you has just started with the presumption that I wasn't an idiot then this whole discussion would've gone a completely different way.

My comments are in response to how I was treated and that is a reflection of the people here, not me.

I didnt take you for an idiot?
I actually asked for more info, you treated me like I had no idea first.
You attacked me for not using google.
I showed you JLR official documents (right or wrong). You couldnt even bother to be constructive about them or question them.

Now to your issue.
To me it is possible/probable the gearbox ECU only looks at, gearbox speed signals along with signals from engine.
Your output shaft speed will not change in relation to the input/crank speed, you will just be going a little faster.
To me all the gearbox needs is difference between input/output shafts and engine speed/load demand, as programmed into the ECU.

Now will it hold 5th locked up is another thing, it probably would but the slightest incline may see it unlock and drop a gear.

We tow alot (well we did, not so much now) the L322 hated to shift into 8th, you either had to break the speed limt for towing, or flappy paddle it. But any twitch on the thorttle would see it change again.

J

 

[RRMaximus]

I didnt take you for an idiot?
I actually asked for more info, you treated me like I had no idea first.
You attacked me for not using google.
I showed you JLR official documents (right or wrong). You couldnt even bother to be constructive about them or question them.

Now to your issue.
To me it is possible/probable the gearbox ECU only looks at, gearbox speed signals along with signals from engine.
Your output shaft speed will not change in relation to the input/crank speed, you will just be going a little faster.
To me all the gearbox needs is difference between input/output shafts and engine speed/load demand, as programmed into the ECU.

Now will it hold 5th locked up is another thing, it probably would but the slightest incline may see it unlock and drop a gear.

We tow alot (well we did, not so much now) the L322 hated to shift into 8th, you either had to break the speed limt for towing, or flappy paddle it. But any twitch on the thorttle would see it change again.

J

I think that what happened was that when you asked me that question I had already had a lot of nasty condescending comments and I was done being nice.

I probably thought that you were asking me for stuff that was not relevant, as a way of wasting my time as part of a condescending attack on my intelligence.

Much like the guy who just asked me here if I guessed if my gearbox was low on fluid before I rebuilt it (which I did not do).

I believe that I thought that you were asking me something that you could find out yourself and I thought that you were asking it to me in order to distract me from my main point.

I apologize for reacting the way that I did, but it was understandable given the ridiculous attacks that I was already dealing with.

The joke being of course that it is clear that I know more than any of the people that have attacked me on this forum.

You are one of the only people who seems to have actual knowledge and I appreciate that.

I came here for some advice, I got attacked, I found it funny responding to the idiots, and I have actually gotten more advice the longer this has gone on, from blob and yourself.

 

[pwood999]

As it happens, RRPhil suggested your gearbox was probably on it's way out due to running low on fluid for a while before you bought it ?

Mine was a simple question with no ridicule, hidden banter, mickey taking, etc. Just a query because diff changes must have some impact on how the gearbox behaves.

I did not suggest good, bad or otherwise.

It does make one wonder if there's a culture clash going on, where you appear to take genuine questions as attacks. They are not.