Gearbox lumpy and clunky

My Discovery has been lumpy and clunky for the last 12 years, I believe this was a common problem with the early disco models, I have managed to live with it by engaging the clutch and accelerator at the right point reducing clunking, its still there, I am interested to know what actually caused this and is there a fix for the problem? Or what can be done to remedial it.

Any information regarding this problem would be appreciated.

Regards

Mike22

Mines the same, it has a very badly worn main shaft and gear.
This adds a huge amount of slack in the drive train making smooth gear changes a art form ,I would never let any one else drive it as I'm sure they would wreck the gear box.
:welcome2:

I see and understand that, you absolutely right, it is an art and you do get to know how to work it, do you know if there is a fix for it? or is it a new box or at least a recon?

Thanks

Mike22

on all the lt77s and early r380s the main shaft splines that mated with input gear splines in transfer box used to wear eventually to the point of complete drive loss ,lr first used a oil thrower just behind pto cover to try and help it before introducing cross drilled gears which is just holes drilled into gear to allow oil from transfer box to lubricate splines which stopped the wear happening,wear allways occurs on both and just changing input gear wont increase the strength of gearbox spline ,input gear been and easy change and on a 1.4 or 1.6 can be done with t/box in situ,as gearbox needs complete strip down its usualy worth reconditioning which is new bearings ,baulk rings ,seals, i dont mind helping somone do their own if they provide the money for parts

Usually this clunk comes from the transfer box(assuming it's an LT230).... it needs an overhaul... especially the Hub and sleeve assy(FTC5099), 4 x thrust washer( FRC6968)and bearing retainer(FRC7970) ... of course if u are already there repace the seals too ... I had the same clunk and after i've overhauled my TB it totally vanished. The parts i've mentioned were completely thread(mostly the washers -- two of them were in pieces) If u can afford make a full overhaul with this Ashcroft Transmissions - LT230 Master Rebuild Kit it contains the parts i said except FTC5099 which is quite expensive but IMO that's guilty for a big part of the "clunk".

If u look at the bottom of the pic u'll see 4 smaller copper washers ... these are FRC6968 and the third part on their right is FRC7970.

Before that i've replaced a front diff, halfshafts, the CV joints and the propshaft UJ's ... the clunk remained there, just a bit improved.... only That TB overhaul cured it for good.Unfortunatelly to get rid of that clunk i dont see cheaper version....maybe some smarter guy

you mean center diff ,which should have new thrust washers fitted,when overhauling ,and selector hub can be turned around so that worn part now sits on low instead of high,but clucking is usually input gear

jamesmartin said:

you mean center diff ,which should have new thrust washers fitted,when overhauling ,and selector hub can be turned around so that worn part now sits on low instead of high,but clucking is usually input gear

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I totally agree... that was the first thing i checked too... strangely on mine the input gear was ok and the clunk vanished after what i did.... the main ideea is that the clunk is from the TB and a complete overhaul will cure it....though this one is quite expensive.

Thanks for the information and posts, unfortunately I don’t have the experience to do it, brakes, timing belt, alternator, general servicing, is my limit, overhaul, out of the question, I use the vehicle regularly, so I don’t want to be without, so what’s the best option with regards cost and time frame.

Who can fix it?

Regards

Mike22

Discovery V8i ES 1995 – LPG conversion 8 years – mileage 87,

it is very common on high mileage boxes for thrust washers to be worn,and can be checked byjacking up one front and on rear wheel and counter rotating props while laying under vehicle one in each hand and feeling wear

Mike22 said:

Who can fix it?


Discovery V8i ES 1995 – LPG conversion 8 years – mileage 87,

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As u can se mr. jamesmartin can ... or u can try aschroft ...what i've said is not for your TB anyway

Hi Guys,

It’s my pride and joy, and in first class condition, lost count of the comments regarding its condition, checking it over each weekend helps, with the current climate, I am considering holding onto her, runs very smooth and no signs of wear, just thought I would enquire as to how to remedy the clunk.

So what will it cost to fix, may as well do the clutch while the clunk is being fixed, cost and time frame, don’t have another vehicle.

So which TB is in mine?

JamesMartin, interested to know what you think?

Regards

Mike22


Discovery V8i ES 1995 – LPG conversion 8 years – mileage 87,

if is that problem £40 input gear ,bearings if needed for input gear £14,£400 recon box £200-£300 fitting £65 ap clutch kit ,you could save £200 on box if you did it your self

Mike22 said:

I see and understand that, you absolutely right, it is an art and you do get to know how to work it, do you know if there is a fix for it? or is it a new box or at least a recon?

Thanks

Mike22

Click to expand...

I have just lived with it, but have a ebay s/h gear box with transfer box which has good splines and gear waiting to fit when the box brakes.
So far the thing keeps going and Ive been all over the place pulling a large 16 ft trailer.
The front diff fell apart the other week and I removed the front prop and I have been driving it around with the centre diff locked.
Today I pulled a total of 3 tons 60 miles just on the rear axle, bloody amazing these old land rovers.
:welcome2:

Hi Guys,

It’s my pride and joy, and in first class condition, lost count of the comments regarding its condition, checking it over each weekend helps, with the current climate, I am considering holding onto her, runs very smooth and no signs of wear, just thought I would enquire as to how to remedy the clunk.

So what will it cost to fix, may as well do the clutch while the clunk is being fixed, cost and time frame, don’t have another vehicle.

So which TB is in mine?

JamesMartin, interested to know what you think?

Regards

Mike22


Discovery V8i ES 1995 – LPG conversion 8 years – mileage 87,

If it has a diff lock its a lt 230 if no diff lock its a borg warner

even though you can and i do fit borg warners to discos they are usually only found on rr

jamesmartin said:

even though you can and i do fit borg warners to discos they are usually only found on rr

Click to expand...

Your right,I was thinking rr :doh:

Its an LT 230 then.

Regards

Mike22


Discovery V8i ES 1995 – LPG conversion 8 years – mileage 87,

Keep looking on ebay for the gearbox and transfer box,then go and check the splines and gear.
I paid about £120 for both in good order.
The other option involves spending lots of money.
I did fit a new main shaft to a lt77 box once, but not an option I would choose now.

the only problem with used r380s is that they usually have worn baulkrings