New recon'd LT230 from Ashcrofts - backlash?

[cipx2]

I just bought a new reconditioned LT230 transfer box (and an R380 as well) from Ashcroft Transmissions.

I did that because the old LT230 on the vehicle was whining and it had an annoying backlash (I bought it like this). The backlash was not from the splines on the input gear - it already had the cross drilled version from factory and it was inspected by me and found to be perfect.

Two years ago I took the 10 bolt rectangular lid off and I found that there was a play between the gears and also the dog teeth on high range gear were a bit worn (and I presume the inner splines on the collar as well).

At that time I said I will try to live with the whine for a while. It was whining between 40 and 60 mph loud enough to bother me and loud enough for people not knowing too much about cars (my daughter, for example) to ask me what's that noise and if it's normal. The noise wasn't as loud as the 300tdi engine but not too far back.

Anyway I managed to lower the whine a bit by using a thicker oil, namely a 80W140.

Time for a new transfer box then.

After I took the old transfer box out, I tried to compare the backlash in both boxes. To my surprise, there's not much difference between them ?

Here are some videos to look at:

- in High range:

- in Low range:

- in Neutral:

Throughout the tests the central diff was locked and I kept the output flanges "in phase", forcing them in opposite rotation directions in order to remove any backlash in the differential itself

Further more, using that steel wire you see in the videos as gauge needle, I compared the total play/backlash between the old and the new boxes. There barely any difference in the amount of backlash.

Now, I don't know if the new box will whine or not but I would definetly have the same amount of backlash in the transfer box.

I don't know how normal is this backlash as I didn't ever lay my hands on a factory new LT230. But I remebered about the episode in the "A 4x4 is born" series where Dave Ashcroft explains how a transfer box works.

I extracted a couple of seconds from the movie where I could hear a 2 stage clonk while his was rotating the output flanges.

Here is the 2 seconds part repeated a number of times:

To my ears, the transfer box in the last movie sound much better than my new one.

What do you people think?

Oh, before someone suggests:

- I already did contact Dave by e-mail last Thursday, nu reply yet; possibly he's still on vacation. No, I don't want to call them in, at least not yet. I'm not from UK and after spending 1.8K pounds on the boxes I need to keep all the unnecessary/avoidable costs down to zero if possible.

- I can't take any of the lids off to have a peak inside and take pics/videos as the new box is on warranty and the old box must be returned in one piece and unopened. I can only do that with Ashcrofts' permission.

[Hybrid_From_Hell]

With ashcrofts reputation.... and more vs a vis ashcrofts reputation when (and if) things go wrong

my advice is wait,... ring, ...speak ...and ask, ...and see what he says...

It is JUST possible there is an issue, ..most likley there is not,

but ...IF there is.... a chat with him without you ferkin about with

things, means Dave will sort with the normal excellent customer service,

If he says that there is not an issue then you can belive him,

so a small wait may be required on your part to be 101% sure.

Nige

[cipx2]

Well, judging by how the box feels in neutral, I'd say the play between the gears is ok or, better said, it sounds/feels acceptable to me (hope it won't whine or at least it will whine on an acceptable level) . Secondly, I don't really mind the play in low range.

It's the play in high range what concerns me.

But, say never mind how small/big the backlash is, how come a new reconditioned box has the same amount of backlash as an old 100k miles transfer box counting that I've seen the wear on the dog teeth in it? This is the question.

I didn't tape the backlash on the old box but I'll do that a.s.a.p. (most likely tomorrow or the day after - I need to drive 10 miles away, where the LR is). I'll do it the same way as in the second part of the High range movie (lock the output flanges to the ground and move the input "shaft" with the wire "needle" on it).

[BogMonster]

I think it is just that they vary. I have driven brand new 110s (delivery mileage 300Tdis) which had more backlash in the transfer box than some 10 year old ones. I don't know what the variable is that makes good and bad ones but it may not be anything that you can do much about and as I have seen, even brand new ones have it so I would suggest it's probably nothing that Ashcrofts have done wrong.

[cieranc]

Just to add, I've spoken to David Ashcroft for technical advice in the past, their customer service is second to none.

I firmly believe that if there is a problem with the 'box (which I think is unlikely) they will sort it without question.

[cipx2]

Gents, I know about Ashcrofts' reputation, there's no question about that.

Before buying from them I've read ALL the web pages/forums/etc where their name is involved, including those not written in English, including quite a few not known to Google.

Everybody is welcome to add some more if he feels like but this is not the object here.

This thread is about the technical aspect, about posting some movies regarding the play in a LT230 (show me another movie like this on the net!), about what to expect when buying a reconditioned gearbox (not necessarily from Ashcrofts), give people something to compare new/old/reconditioned boxes to etc etc.

We'll see if that's a normal play or not and I have no doubts the matter will be cleared one way or another (unlike my adventure with Beamends).

[Bush65]

IMHO the backlash indicated in the video clips is good.

Principally it is the backlash in the dog clutch that you are looking at. The dog clutch is manufactured with large backlash to make engagement easier.

Excessive backlash between gear teeth would be a cause of concern (indication of wear, which causes noise etc.), but normal backlash in the dog clutch is not.

[ciderman]

That as Bush 65 has already confirmed is very normal and by the look of the operation on your video I would say its a nice tight box .

[cipx2]

I also suspect the majority of the backlash comes from the dog clutch. It's the play between the selector sleeve and the hub plus the play between the selector sleeve and the dog teeth on the high (or low) range gear.

From memory, on the old box:

- the hub looked like this

-the sleeve wasn't too far from this (although I couldn't see it as pictured as I didn't take it apart):

- and the dog teeth were worn in a degree similar with the hub pictured above (maybe a little bit more but not like on the sleeve).

My only concern is that the new box will clonk same as the old box, otherwise everything will be fine (well, presuming the play between the gears is fine and it won't whine).

[Bush65]

I also suspect the majority of the backlash comes from the dog clutch. It's the play between the selector sleeve and the hub plus the play between the selector sleeve and the dog teeth on the high (or low) range gear.

From memory, on the old box:

- the hub looked like this

...

Not quite like that. As I said above every second tooth is removed. This makes the space between teeth on the male part, over three times the thickness of the teeth on the female part. This results in the backlash that you are seeing.

[cipx2]

Now that was funny ...

What you are saying is that if LR would have chose to remove all the dog teeth but one from the high or low range gears then the play would have been 360 degrees minus the width of one tooth measured in degrees. That's not true.

Even with only one tooth, that tooth will only have the play given by one space between splines in the sleeve (pictured above) or female tooth as you put it. There are no splines removed from the sleeve so no matter the number of dog teeth removed on the gears the play is the same.

Here is a picture of the parts involved, from left to right: low and high range gears (red arrow points to the dog teeth), sleeve (blue arrow points to the female teeth) and other bits - click on the picture if necessary:

There are 16 dog teeth on either gear and 32 splines (female or male) on the sleeve.

In case it's still not clear for you, I suggest to draw a rough section of the sleeve and the dog teeth in their working position on a piece of paper (meshed together) and it will all become clear.

As an update, it seems Dave somehow missed my initial e-mail. I contacted someone else from his staff asking about Dave (I thought he was missing) and Dave replied within 15 mins or so. He was kind to answer my questions and give me the details I was asking for. We're still in the middle of it (actually more towards the end). I'll post further updates.

[white90]

Cipx2

I am sure you do not mean to come across as you are doing

but a read of your posts before you post,

may save the underlying tone

that is common across a few of yours recent postings.

It is very easy to type stuff that reads not to well.

Members are trying to assist you and you come across not the best.

[cipx2]

Will do.

Update:

- Dave was kind to let me look inside the box.

- as I suspected, the majority of the backlash comes from the high/low range dog clutch.

Pictures:

[ajh]

Does this mean that on a 2x4 converted box the backlash is gone? I know they do the conversion but I have never seen how they go about doing it and am not familiar enough with the power-route through the box to guess at it.

[cipx2]

The transfer box has 2 parts:

- the differential part (allows or not a different rotation speed beween the front & rear prop shafts/axles), and

- the speed reducer (from where you select the high/low range)

The 2WD conversion involves mods at the differential part level. The reducer part remains untouched.

The backlash this thread is about takes place exclusively at the reducer part level. Doesn't include the (potential) backlash in the diff part of the transfer box.

For what the 2WD conversion involves you can follow the links in the dedicated thread from the tech archive: http://forums.lr4x4.com/index.php?showtopic=8187