LT77 rebuild?

[123rover50]

The young fella here has a 92 tdi with 400 thou on the clock.
It crunches going into second gear but I can change it OK if taking it slowly but he says its hard when taking off from lights with someone right behind. If he fluffs it he has to stop and start again.
He wants to pull the box and as he is not mechanical guess who gets the prize.
I know nothing about modern boxes and the Rave The Landy CD 1.1 for the Disco doesnt even mention the LT77.
I have done series boxes but has anyone done their own LT77?
What manual is used?
I had a look at the other Raves but they dont mention the LT77 either.
I believe special tools have to be used. Is this right?
Didiman

[justinc]

I would definately upgrade to a 300Tdi R380 gearbox at this point.

The LT77 is quite exxy to repair, and they are difficult to get shims etc for now. The 300Tdi R380 is a direct fit to a 200 Tdi Disco, 200 tdi defenders are a different story, though.

JC

[MacMan]

I have an LT77 that is 95% of the way through a rebuild, but as Justin says access to a shim library is the problem. Not even LR Australia keep them in stock and they're something like $25 a throw, so doing a fit/try selection is problematic. Precisely why mine remains in numerous boxes on the floor of the garage. :o

[Hymie]

I would definately upgrade to a 300Tdi R380 gearbox at this point.

The LT77 is quite exxy to repair, and they are difficult to get shims etc for now. The 300Tdi R380 is a direct fit to a 200 Tdi Disco, 200 tdi defenders are a different story, though.

JC


Now that's interesting.
When the LT77 died in my Disco up in Kunnunurra a well known Landrover Parts mob tried to sell me an expensive adapter kit to fit an R380 to the 200Tdi.
I bypassed them and found a good LT77 in a wreck and had it freighted up.
Guess they missed out on a sale.

[justinc]

Done a few Hymie, Direct swap but IIRC the clutch pushrod is different length? It is probably safer to buy a new pushrod to suit a MA series 300tdi disco R380. Part number is FTC3912.

JC

[isuzurover]

I agree with JC.


Now that's interesting.
When the LT77 died in my Disco up in Kunnunurra a well known Landrover Parts mob tried to sell me an expensive adapter kit to fit an R380 to the 200Tdi.
I bypassed them and found a good LT77 in a wreck and had it freighted up.
Guess they missed out on a sale.

From my research, there are only a couple of bolt holes difference in the bellhousing between 200 and 300 tdi. Nothing 5 minutes with a drill won't fix.

[justinc]

Actually Ben, no drilling req for Discos, just removal of 1 stud IIRC,

Easy peasy :)

JC

[PV5150]

I just rebuilt my LT77S in my 93 D1 last week. Mine was the same as your sons - 1st to 2nd gear change would chirp if I was a little too ambitious at the lights, and 3rd to 2nd when changing down would crunch. Other than this the box appeared perfect, When we pulled the box apart the 2nd gear thrust washer had split in two, and this is what reportedly caused the issue (and is a known weakness (http://www.ashcroft-transmissions.co.uk/index.php?act=viewProd&productId=217) in the box).

Broken thrust washer (http://img.photobucket.com/albums/v229/PV5150/20130116_122928.jpg)

I had rung MR Automotive here in Brisbane and a reconditioned box (unfitted) was going to set me back $2500 and a further $800 for them to fit it. So I decided to bite the bullet and rebuilt the box with the assistance of a diesel mechanic friend of mine, his workshop and 4 post hoist.

The rebuild kit was purchased from my good friends at FWD Automotive (http://www.fwdmotors.com.au/index.html) here in Brisbane and the parts came to around $600 ($300 for gaskets, bearings, circlips, oil seals etc, and a further $300 for baulking rings, synchro's etc).

For reference purposes, I used the Defender LT77S supplement (downloadable .PDF on the net at around 2MB) and a guide for the LT77 rebuild here (http://forums.lr4x4.com/index.php'showtopic=52887). The tools that you need are listed in the Defender workshop manual, and some of these will include: bearing and gear pullers, pointy nosed pliers, circlip pliers, feeler gauges, hammer and large sockets for tapping gears back into place...Oh and a gas axe (to heat, not cut) for removing the large seal on the front of the input shaft.

Image 1 (http://img.photobucket.com/albums/v229/PV5150/20130114_160110.jpg)

Image 2 (http://img.photobucket.com/albums/v229/PV5150/20130114_160211.jpg)

Image 3 (http://img.photobucket.com/albums/v229/PV5150/20130114_160312.jpg)

Image 4 (http://img.photobucket.com/albums/v229/PV5150/20130114_160250.jpg)


Does the gearbox have a lot of backlash? If so, you may need to purchase a new main shaft (splines may be flogged out) and that will add a bit to the final build cost - to the point where it may be more cost effective to get a second hand R380. As has been said previously you will need shims for setting up end float and we were fortunate enough to have some in the workshop. Happy to help where I can.....

Regards

Matthew :)

[123rover50]

Thanks for that. Its an H suffix box and we pulled the back off. The splines on the shaft are a little bit worn but the gear splines are good. Think it must have been replaced sometime. The kit sounds good so will contact FWD. I have all those tools and the Disco book with the LT77s in it so may give it a go.
Another thread here says that the 5th gear shaft bearings for the R380 are not made any more:( So perhaps its good to stick to the LT77.

Didiman

[PV5150]

My pleasure :) My box was H suffix also. If you need help then please don't hesitate to ask

[wlb]

The LT77 in my 1987 3.5L Rangie has been slow to shift into 1st and 2nd for years, but it's getting noticeably worse now. I can't really complain as it's done 460,000km.

The oil leaks have been largely fixed but the transfer case still leaks.

Will the R380 fit and does it use the same transfer case?