LT230T Rebuild Questions

[Max Headroom 2.3m]

Hi all, I seem to have a bit of time lately so finally got around to ripping out the fender’s TC for overhaul. It had a bit of a wobble in the rear output flange, a couple of oil leaks and intermittent difficulty getting the centre diff to lock. After opening up I had a couple of answers and a couple of surprises.[biggrin][bigsad]

The clearance in the rear output flange I thought was due to a knackered bearing but turns out to be a lose flange nut. Bearing was fine so immediate thought was put on a new nylock and torque down properly. However after pulling of the rear flange I found the spline was rusty and had a bit of back lash (guess 1-2 degrees). I think the forward and backward movement would eventually loosen any nut, no matter how tight so not the answer. A new rear main shaft is about $500 plus flange plus shipping (Ouch). Soooo my question is…is it a done thing to put the old one back together with Loctite retaining compound on the spline or do I bite the bullet some more and replace? Also the truck has a 50mm lift, would that contribute to any dramas here?

The intermediate shaft stake nut was also not very tight. It was staked at some point but had rotated slightly so that the staked bit was now jammed on the thread next to the recess in the shaft. Result; bearings loose and inner races able to rotate on shaft which is showing some wear. It appears that the ensuing vibrations had started to damage the front casing hole and I suspect the source of one of the oil leaks. I have an Ashcroft S/S sleeve to bore and fit to fix that one. I think I got to it early as the wear on the shaft is not too bad but I will replace the intermediate shaft. Other than genuine LR, I could only find Britpart or Bearmach but no OEM. Would Britpart be OK for this (it’s just a shaft)? I also have a solid diff cross pin and new Ashcroft 1.3:1 high range gear set to go in. Has anyone else fitted one of these and are they happy with it.

It appears that the intermittent CDL problem was due to a rusty spot on the detent ball. In some positions the ball would retract and let the CDL engage but with the rusty spot in a certain position it would jam and not let the CDL shaft go across preventing CDL locking. Mmmm, easy fix – replace the detent ball, nice and cheap. Getting the old one out was a bit of a sod, it kept jamming in the bore so strong magnet trick didn’t work. I ended up using the hooky bit of a steel tent peg, pushing real hard from inside. Question is how on earth did it get rusty in such an oily environment inside near top of front output housing. There is a bit of rust on the inside end of a screw-in plug located next to the CDL switch. However none of the other internal components have any evidence of rust and the oil out of the transfer case wasn’t milky.

I would appreciate your views and apologies for the long post, clearly way to much time on my hands.

[workingonit]

A new rear main shaft is about $500 plus flange plus shipping (Ouch).

I have an Ashcroft S/S sleeve to bore and fit to fix that one. I think I got to it early as the wear on the shaft is not too bad but I will replace the intermediate shaft.

...detent ball. Getting the old one out was a bit of a sod, it kept jamming in the bore so strong magnet trick didn’t work. I ended up using the hooky bit of a steel tent peg, pushing real hard from inside.

Try companies like MRAutos Bris for second hand rear main shaft.

Have seen youtube vids where worn splines (not LR) have been bulked with some sort of two pack resin. Also seen threads where guys have rebuilt axles splines (not LR) with weld and hand ground, pulled years later for a look and still going well! Depends if you always travel with mates to tow you home if such remedies fail.

Dentent ball bearings. The hi/low shaft and the lock/unlock shaft have different diameter grooves, 1/4 inch and 3/8 inch from memory, but LRover use the 3/8 balls for both shafts. So the 3/8 ball rides too high in the 1/4 inch groove. I don't know if there is an engineering principle or an accounting principle behind LRover using one sized ball for two different sized grooves. I replace the 3/8 ball for a 1/4 inch ball on the 1/4 inch groove.

As you have found, the ball does not travel right through the bore hole - you have to use a probe inside the casing to free the ball. I don't know if again there is an engineering principle behind having a tapered hole - I can only guess they don't want the ball falling into the case if the shaft were pulled out - but what the heck, you are in there anyway with plenty of access to retrieve it. I can't see the sense of the grub screw pushing the spring pushing the ball against the end of the tapered hole, instead of on the shaft. Rightly or wrongly I drill through these tapered holes to allow the ball to exert its full force on the shaft. Had a situation where no matter how tight I screwed the grub screw the selector was always unlocked by the slightest rattle of the selector stick - solved by drilling through the tapered bore hole.

Ancient Mariner has a method of dealing with the leak at the front of the intermediate shaft where it leaks after the o-ring fails. He drills and taps a hole at that end then uses the hole to pull tight another cover. I've done my own mod, yet to prove it works as the vehicle is not yet together. I also drilled and tapped a hole as per Ancient M. I then screwed in a tensile bolt and milled the head to a taper (the male). I then made a cover plate with female taper to mate with the male taper. Was a bugger to do. But in theory both ends now have their oscillations - up and down movement - controlled. The stainless insert will save the aluminium housing from ovaling, but I can't see it being a solution to the constant 'mashing' of the o-ring and leaking again.

[Max Headroom 2.3m]

The hi/low shaft and the lock/unlock shaft have different diameter grooves, 1/4 inch and 3/8 inch from memory, but LRover use the 3/8 balls for both shafts. So the 3/8 ball rides too high in the 1/4 inch groove. I don't know if there is an engineering principle or an accounting principle behind LRover using one sized ball for two different sized grooves. I replace the 3/8 ball for a 1/4 inch ball on the 1/4 inch groove.
I measured the grooves using drill shanks with the three Hi/Lo grooves being closest to 8.5mm dia and pretty deep. The two CDL groves were 8.0mm dia and a fair bit shallower. My casing bores for the detents were both a touch over 9.0mm dia and straight bore but less than 9.2mm (assume 9.1) and the detent balls that came out of the box both measured 9.0mm dia.
160467
You can see in the above photo how rusty the left ball is which came out of the CDL detent and given the close tolerance it wouldn’t take much to jam it. I like your idea of using a smaller ball for the CDL.
160468160469
I compared the original 9.0mm ball with using a 1/4 inch (6.25mm) ball and definitely penetrates deeper. Given that the casing bore measured at 9.1mm does the ¼ inch ball allow more slop? I guess it is easy enough to try and if I am not happy can change back as it is accessible from underneath when the TC is back in the vehicle. I guess the take-home message is definitely clean the bores with a 9.0mm drill and test by dropping through a good condition/new ball before reassembly.


I don't know if there is an engineering principle or an accounting principle behind LRover using one sized ball for two different sized grooves. I replace the 3/8 ball for a 1/4 inch ball on the 1/4 inch groove.
I suspect it was a human resources principle behind this. If you have two different balls to choose from, it will only be a matter of time until someone stuffs it up.



Ancient Mariner has a method of dealing with the leak at the front of the intermediate shaft where it leaks after the o-ring fails. He drills and taps a hole at that end then uses the hole to pull tight another cover. I've done my own mod, yet to prove it works as the vehicle is not yet together. I also drilled and tapped a hole as per Ancient M. I then screwed in a tensile bolt and milled the head to a taper (the male). I then made a cover plate with female taper to mate with the male taper. Was a bugger to do. But in theory both ends now have their oscillations - up and down movement - controlled. The stainless insert will save the aluminium housing from ovaling, but I can't see it being a solution to the constant 'mashing' of the o-ring and leaking again.
I like your idea of putting an extra sealing cap on the outside of the front intermediate shaft casing bore and if I understand it correctly you have it screwed into the end of the actual shaft (that centre bore is just screaming out to be drilled and tapped). With the tight tolerance of the S/S sleeve, any vibrational movements would be minute A decent thickness of silicone goo (or second O-ring) under that cap should absorb the movements and even if it does fail over time, it would be easy enough to replace in situ.

[rick130]

O rings can take a set and harden with age, but there'll be no movement if the bore of the bush is matched to the shaft, it should be a firm push fit.
Just make sure you put a lead on the bore or you'll at a minimum damage the O ring, or not be able to get it in without tearing.
Made that mistake....

[Max Headroom 2.3m]

O rings can take a set and harden with age
The original intermediate shaft O-ring is a case in point. The appeal of the end cap is that it can easily be changed as often as needed.

Agree with the lead. The Ashcroft S/S bush comes with a nice one already, as well as a small lead on the outside of the bush for when it is pressed in.

EDIT

160539
Ahh…yes. The end cap would be a good idea except for the fact that the gearbox partially covers the front of the intermediate shaft when bolted up. I knew that [bigrolf]!