Jump to content

R380 gearbox rebuild


cipx2

Recommended Posts

Hi everyone.

My 1998 disco 300 Tdi with about 100k mi on the clock has a gearbox noise, mainly in the 4th gear under load and between 50 and 60 km/h (30-37mph).

It had it since I got it, some 2000 mi ago, so I knew something is fishy around there somewhere. Since it's not my everyday drive it took a while to make some tests and come to the conclusion that the gearbox is to be blamed for the noise.

Other than the noise, the gearbox works just fine, no problems when changing gears, no other gear noises.

So I believe I can get away with a set of shaft bearings (7 pcs) and a couple of seals.

I attached a recording I made with my pda, not entirely reflecting the real noise but just to give you some sample of it.

The recording was longer but I cut it short to where I used only the 4th gear and I'll explain it a bit:

- 1st 5 secs is where I push and ease the throttle a bit

- next 5 secs is where I lifted the foot off the accelerator (engine break)

- the rest is where I kept the speed steady by using the left foot on the break and using the accelerator to load the gearbox.

LE: since there is no reply as yet I added couple of more questions:

1. A first question that I have is if anybody done that. Or had the same symptoms.

2. What chances do I have for getting the right shaft(s) play with the original shims? Do I need to get two sets of shims also, just to be on the safe side?

3. Are there other parts in the gearbox that I should change (o-rings, ... - other things that are cheap and worth changing) ?

MLE: added a second sound recording of full 1-2-3-4 gear change. There are some parasitic noises when shifting gears due to the fact that I tool some screws away from the center console, the gaitors were lifted up and my pda was on the (loose) console.

4th_gear.mp3

1234.mp3

Link to comment
Share on other sites

I took the gearbox out yesterday.

Anybody interested in the progress of striping it and putting it back together (hopefully in the right way :))?

ABSOLUTELY!! - I'm taking my R380 apart in a couple of weeks time, so any 'advance warning' of gotcha's will be very welcome.

Cheers

Dunk

Link to comment
Share on other sites

I was beginning to think that I'm using this thread to talk to myself :)

Anybody else interested?

The progress will be slooooow since i'm rather busy these weeks at the office (I'll work weekends too) and I decided to do this in my father's garage 10 miles away. On top of that it usually takes about 10 days to get the parts, so ...

First of all let's see what gearbox are we talking about:

gbserialuk2.th.jpg

It's a R380 55A (Type B ) suffix J gearbox.

I already took out the selector housing so no pictures I'm afraid. Maybe I'll put it back to make some..

First "gotcha" is to take the oil seal collar on the output shaft that needs the special LR tool. I tried using some other 2 extracting tools but with no success. It's true that I didn't "push" them too hard as I knew I have the option to go to a LR shop and borrow the tool.

I'll do that this evening.

One thing I need to know from you guys. What names should I use for the shafts in a 3 shaft gearbox:

1. Input shaft, Output shaft and Intermediate shaft, or

2. Pinion Shaft, Main shaft and Layshaft?

Which ones are the most used ones in UK? So that I can speak the same language. By the way, English is not my native language so please excuse my mistakes and also please correct me if I choose the wrong words ...

Link to comment
Share on other sites

One thing I need to know from you guys. What names should I use for the shafts in a 3 shaft gearbox:

1. Input shaft, Output shaft and Intermediate shaft, or

2. Pinion Shaft, Main shaft and Layshaft?

Which ones are the most used ones in UK? So that I can speak the same language. By the way, English is not my native language so please excuse my mistakes and also please correct me if I choose the wrong words ...

Well, I never noticed that english wasn't your first language, so I don't think you have too much to worry about!! - where are you, and what IS your first language?

In answer to your question - my preference would be option '2' as that's the names they use in the official LR R380 re-build manual, which is what I'll be using as my guide.

Many thanks in advance - and good luck!!!...... I'll be keeping a close eye on this thread :)

Dunk

Link to comment
Share on other sites

This is the oil collar we're talking about:

dsc00449yh8.th.jpg dsc00450cq4.th.jpg

One can notice the black stuff around the main shaft oil seal and around the oil pump. In the past some wise guy thought it could stop potential oil leaks. I can admit that around the oil pump could help a bit but around the oil seal is completely useless. Well, more cleaning job for me...

I decided to take the gearbox to the shop (just to save some time). Since I was going to replace the collar anyway (3 quid), together with the oil seals, we used a different tool which is much stronger and easier to work with:

dsc00452kq9.th.jpg dsc00453nh7.th.jpg

I must say that the collar broke loose with a real bang. It sounded like it was epoxy glued in place.

Next thing is to remove the extension housing after taking out the spool retainer (red arrow in the picture below) and the bolts all the way around (most of them have bi-hexagonal heads). No problems here.

dsc00448km8.th.jpg

After taking out the extension housing, the next step is to remove the bearing track from the end of the layshaft (#1 in picture). I used a regular three leg puller, plenty of space to grab hold of it.

dsc00455kk6.th.jpg

Underneath the bearing track there's the nut that needs to be took out. I got it straitened back with a pointed squarish tool and undone it nice and easy with the impact air gun. I took the 5th laygear out after that (with the split washer).

I took out the bearing track from the main shaft. This one is not so tight on the main shaft so I used the gear underneath it as a slide hammer to drive the track out. Bumped it 6-8 times and it was out. But I had to remove the washer and both the semi spacer/lockers that keep the pinion in place.

I placed all these last bits I took out and took a picture, just for reference:

dsc00457rm2.th.jpg dsc00460yn3.th.jpg

Next thing is to remove the screw that secures the yoke. It is locked in place with some thread locking stuff so it needs some heat. 20 secs of hot air blew with a 1800W heat gun were enough. It came out like it was screwed in cheese. The manual says that this screw needs to be replaced (which I won't - it looks as new and I took it out without any damage).

dsc00470il5.th.jpg

One last screw (a T40 torx I think):

dsc00471gc0.th.jpg

Then everything can come out (except the intermediate reverse gear - I don't need to remove that).

LE: forgot to answer, my 1st language is romanian.

Link to comment
Share on other sites

Good work - keep it up....... it's the next bit that I'm most interested in as it's my 2nd gear synchro that's busted <_<

Dunk

(PS - Your english is WAAAAY better than my Romanian..... probably better than my english too :lol: )

Link to comment
Share on other sites

Thanks :)

Next thing was to remove the center plate with a bit of tapping from underneath until it breaks loose from the sealant. Then I took out the two 10mm head screws from the plate shown in the picture above where the torx screw is taken out.

Then the mainshaft, layshaft and the yoke can be extracted as a whole unit. No worries here. The pinion shaft is the last thing to come out.

Some pictures:

- pinion shaft:

dsc00485hd7.th.jpg dsc00484hj3.th.jpg dsc00482jr2.th.jpg dsc00483ce0.th.jpg dsc00479uf4.th.jpg

-the bearing track on the mainshaft that goes in the center plate:

dsc00477yp1.th.jpg

- layshaft:

dsc00473fv1.th.jpg dsc00488wm7.th.jpg dsc00490jt8.th.jpg

Link to comment
Share on other sites

I took out the front plate (sometimes called "nose cone"?) and the nasty surprise showed up!

dsc00491ag3.th.jpg dsc00492xt7.th.jpg

What you can see there are two handmade shims, put under the bearing tracks in the front plate in an attempt to set the layshaft and mainshaft/pinion shaft end float right.

I wonder what sorrow a@@ ......(fill in your worst) .... grease monkey could do that?! I hope I never find out 'cause I'd brake his hands ...

Sorry for this but I'm really upset.

Link to comment
Share on other sites

My guessing is that, in the past, someone replaced the front bearing on the mainshaft (and maybe the one on the layshaft) by taking out only the front plate (I think it can be done this way). One thing that tells me that is that on one bearing it says Timken - England and on the other on it says Timken - France ...

Well, the life must go on ....

There is one thing that puzzles me. Each synchro sleeve has a notch in the form of 1, 3 or 5 half moon stamped on a side.

They're easy to spot in a previous picture:

dsc00490jt8.th.jpg

According to the manual these notches identify the synchro assembly to their corresponding gears:

- the one with 1 notch faces the 1st gear

- the one with 3 notches faces 3rd gear

- the one with 5 notches has to face 5th gear.

In the above picture both syncros face the right gear, so everything is according to the manual.

BUT the 5th/Reverse synchro was facing the reverse gear instead of the 5th!

These pictures show the synchro in place, before taking anything apart:

dsc00454fn7.th.jpg dsc00456nj8.th.jpg

And this one before taking the synchro out:

dsc00469jn8.th.jpg

It's blurry but it's easy to see that the synchro hub has two notches pointing upwards (towards the 5th gear). The synchro hub has only one notch that has to be on the same side with the notches on the syncro sleeve. As there's only one way to assemble the syncro hub and the sleeve (they don't fit any other way, even if u turn one of them 180 degrees) this means that the 5 notches were facing the Reverse set of gears.

Does anyone know the answer to the puzzle? thanks in advance.

Link to comment
Share on other sites

Dunk, I don't plan to take all the bits and pieces out from the mainshaft as yet. Even if I'll replace the bearings. Everything worked ok, everything feels and sounds ok so I have no reason to take them apart. What I will do is check the end floats all around.

What I can do is take the 5th/reverse synchro to pieces (I previously did that anyway) and take some pictures. If this is what you'd be interested or if there anything else you'd like to see, let me know.

I managed to find another recording of the noise the gearbox made in my archive. This time a full 1-2-3-4 gear change can be heard.

I attached it to my 1st post in the thread.

Link to comment
Share on other sites

Dunk, I don't plan to take all the bits and pieces out from the mainshaft as yet. Even if I'll replace the bearings. Everything worked ok, everything feels and sounds ok so I have no reason to take them apart. What I will do is check the end floats all around.

What I can do is take the 5th/reverse synchro to pieces (I previously did that anyway) and take some pictures. If this is what you'd be interested or if there anything else you'd like to see, let me know.

I managed to find another recording of the noise the gearbox made in my archive. This time a full 1-2-3-4 gear change can be heard.

I attached it to my 1st post in the thread.

That'd be great - don't go to too much trouble, just for me though!!!...... the stuff you've done so far will be a big help. Are you going to continue to do pics and stuff for the re-build now you've stripped it down?

I guess a lot of the pics would be pretty much the same - maybe anything that's a particular problem.....

Many thanks for this lot - you're making me feel much more confident about doing the job myself!! :D

Dunk

Link to comment
Share on other sites

No trouble at all. I'll do that next time, on w/end most likely.

Yes, I will try and take pictures further on. Unfortunately I don't have someone around to take pictures for me. I usually wear gloves but sometimes I don't and, since I don't wanna cover up my phone in oil, not every step was shown. But nothing essential is missing.

Now I'm a middle of a dilemma: to replace or not to replace the bearings. I see two alternatives:

1. They don't look so bad. Counting the fact that I will not put more than 3-4000 mi a year on this disco, I think there is a good chance for them to perform well for another 5-6 years. What looks more appealing to me is to try to find a suffix L R380 gearbox from a wrecked D II in the near future. So I'll redo the shimming, put it back and start looking for a replacement GB (not right away though). This way looks more cost effective on the long term.

2. On the other hand, I would like to do the job right and replace the bearings (oil seals etc.). So that I'm fully satisfied with my work and time spent. There is a good chance for this gearbox to perform well another 10 years with a new set of bearings, proper care and only 3-5000 miles a year, after which probably everything will go to the scrap yard anyway.

This is what I need to sort out the next few days. For now I'm 50/50 into replacing the bearings or not.

Link to comment
Share on other sites

I really can't make up my mind on the above dilemma.

Does anyone have a word of advice for me, please? Should I change the bearings or keep them?

Personally, I'd change them, just for the peace of mind and the satisfaction of doing 'a proper job' (unless it's a LOT more work and/or a LOT more expense ;) )

Dunk

Link to comment
Share on other sites

Thanks for the advice guys. And thanks for dropping in Tonk.

All righty then. Bearings change it is.

It's not much more work to change the bearings compared to what it takes to get to them. I think that, with proper tools and experience, this can be done in less than half an hour. It will take me longer but not more than 2 hours I guess.

As for the expense, they will cost me about 130 pounds, delivery and VAT included. I can't comment on that 'cause in these parts of the world a sterling pound weighs different than in UK.

Link to comment
Share on other sites

Since this is about the time I hope the parts will get here, I don't think you'll miss anything.

I'll post the pictures I promised though, the ones with the 5th/reverse synchro taken to pieces.

Well, enjoy your trip regardless the reason you're going there...

Link to comment
Share on other sites

  • 2 weeks later...

Just a quick update:

- bearing set and other bits arrived 3-4 day ago

- no problem replacing all of them except the outer track from the intermediate bearing (between the pinion shaft and mainshaft):

dsc00479uf4.th.jpg

I tried with a 3 leg puller (a quite nifty one, with a cone that held the 3 legs/claws spread) but with no luck. I couldn't find the proper tool at any of the LR shops in my area. I was thinking to have a tool made for the job but, since I don't think I'll ever need it, I changed my mind and went to a guy 5 mins from home who has a lathe. So I had the track cut from the pinion shaft and, since I lost the old bearing track, the guy made me a tool to drive the new track in place.

- two things I needed to be careful: make sure the everything is clean when driving the bearings and drive them all the way.

- I cleaned up the mating faces on the front cover, main cover and intermediate plate; put the bearing tracks that go on the front of the main casing, assembled the front plate to the main casing (no silicone and without the oil seal)

- I put the layshaft in place, screwed the intermediate plate in, used a mallet to make sure all the bearings are home and roughly checked the play: no luck; the layshaft had no play; took the layshaft out, put the pinion shaft and the mainshaft in place; same luck: the mainshaft had a play of 0.19 mm (the play should be 0.1-0.6 on both shafts)

- nothing to do on the shim for the mainshaft but to order a new thicker one or have it made.

- the shim on the layshaft was not so far from what it was needed so I used two feeler gauges placed between the main casing and the intermediate plate to see how much thicker is the original shim; I found out that it was only about 0.05 mm too thick; thinking that I don't have anything to lose, I sanded the shim on sand paper (started with 100 then 180 and 400) placed on piece of marble; I sanded it on one side only (keep the other untouched); as a last touch I used the marble itself since the surface was not finished, just as it came from cutting; I must say this is tricky, you have to rotate the shim often, make round movements and you'll sand some of your own skin from the fingers as well; in fact, the tricky part is to do this evenly, measure it from time to time in different places so the difference in thickness around the shim is to be kept less than 0.01 mm; it took me about 40 mins to make it 0.06 mm thiner and the thickness varies with only about 0.003 mm;

if you have to do this, better have it done on a machine; I did this because it all started from a joke my father said that ended with a wage saying that I can't do it; well, he lost and has to pay the beer for the whole summer :P; he's lucky that I don't drink much ...

- I put the shim in place and measured the play on the layshaft: 0.02 mm = perfect (this is what i chose as the target value).

- As for the other shim, the one on the mainshaft, I'll probably order 2, the one with the thickness resulted from measurements and the next thicker one, just to be safe, to have one machined if necessary (no more skin on my fingers to spare I'm afraid :P).

From now on, everything has to go smooth, I don't expect anything tricky on the way. One piece of advice, maybe: don't be tempted to drive the oil collar in with a hammer, this will damage the bearings. Use a tool similar with the one in the manual or a hydraulic press.

If I'll find something worth noticing I'll post it here. If not, this is as far as I'll go with this thread.

This thread wasn't meant to be a howto/tutorial or a replacement of a repair manual. I stripped my gearbox 'cause I had a small problem and considered it to be part of the hobby. Since there are not too many places on the net to see pictures of what's inside and how to do this and that, I considered it wouldn't be such a bad idea to post something on the subject.

If someone else has questions, feel free to ask.

Dunk, you have PM about the pics you were interested in.

Link to comment
Share on other sites

  • 1 year later...

Bit late to see this now but I am in the middle toppof rebuilding the same box & noted exactly the same thing with the 5th/REV gear notches. The 5 notches faced the rev gear & not 5th. My first theory was that maybe someone had swapped the Hubs for the 3rd/4th gear which look identical. but doesn't help.

My conclusion now is that the manul is wrong wrt 5th/REV gear only.

The main point is that the side with the notches should align with the single slut in the hub. You can't actually turn the sleeve around anyway as they have master splines to the hub.

Link to comment
Share on other sites

  • 2 years later...

So reviving an old topic.... I'm currently in the process of stripping down a 'supposedly recon' gearbox for my disco as the old 1 has got a bit notchy. I am faced with a bit of a dilema. Most of my dealings with Land Rovers have been of the series variety and I have rebuild quite a few series 1/2/3 gearboxes in my time (and as such know them like the back of my hand) - they are easy and can be stripped down in a couple of hours. Coming to the R380 I have found it much more difficult to start with although a I have a workshop kitted out with some specialist tooling more than the average, nothing is proving to be simple. Anyway, my plan was, as this was reputedly reco,n it would need very few items replacing and I would just check it over and replace the seals where necessary for piece of mind. First impressions are that the syncro/baulk rings looks slightly worn on the outer teeth although I havnt finished fully stripping it and inspecting all. What I'm after is a bit of advice of how to next proceed. Am I likely to get away with a set of syncro rings at a minimum or if any more items are required through unavoidable damage on dissasembly or otherwise is it going to be more cost effective to buy a complete rebuild kit circa £180??? A few pointers would be very helpful.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy