Registry of Ex Military Land Rovers

REMLR Technical => Mechanical => Topic started by: Hufav on May 12, 2018, 08:20:30 PM

Title: Suspected centre diff bolt failure LT95
Post by: Hufav on May 12, 2018, 08:20:30 PM
First I like to thank Tristan and Bearman for their phone support today. Being in a state of devastation this arvo it was very good to get a bit of there-there and good advise of course.
I have an RFSV that I've owned for just a matter of months and have been working through a few larger service items and on the list of things to do was loctiting the centre diff bolts. Too late though as I suspect they let go today. It started with a strange little squealing  sound under load but before I could get my head around what it might be and where it was coming from (30 seconds later say) the sound became a lot more alarming and in went the clutch and I pulled over. Luckily (there's the eternal optimist speaking) I wasn't that far from home and 90 bucks later I was laying underneath it in comfort of my own driveway. So straight up I noticed a hair line crack in the output housing and a fair amount of play in the centre diff. when i got it of the tilt tray I gently drove it back and forth to determine what was happening. The squealing sound was accompanied by a rattle like a bag of nuts and bolts. All gears are easily selected with no notchieness so I'm praying the gearbox itself ok. Please don't tell me I'm dreaming!
While at this stage, before I pull it down, I am only assuming that was the cause of the problem. However it would probably be safe to suggest to anyone who has this job of loctiting the centre diff bolts on their to-do list, maybe put it at the top, in highlighter. I know I'm not the first to have this problem and this has been documented previously in this forum but for something that causes such a catastrophic failure yet is such a simple mitigation process I think it warrants repeating.
This truck is my daily driver and work truck. I absolutely love driving it. Every time I hop in it puts a smile on my face. Unfortunately I lost the smile today. It'll be back though, I know it!
I'll pull it down and take a few shots to include in a full report. Till then.....
Title: Re: Suspected centre diff bolt failure LT95
Post by: Rob6x6 on May 12, 2018, 11:50:54 PM
Stick with it mate. I would like to know the outcome.
Cheers Rob
Title: Re: Suspected centre diff bolt failure LT95
Post by: Hufav on May 13, 2018, 03:53:31 PM
Cheers Rob.
Being mother's day I could only sneak in a couple of hours. Which should have easily been enough but over torqued drive shaft bolts on the rear of the front shaft slowed me up  >:(. I threw the towel in early as I'll have to cut off one that wouldn't budge. Found a lot of backlash in the front axle so a heavy-duty kit will go in there. No doubt the drive flanges are flogged out. Rear axle has none at all. I'll have a proper go tomorrow
Title: Re: Suspected centre diff bolt failure LT95
Post by: P6X6 on May 14, 2018, 04:43:18 PM
Thanks very much Hugh.

I’m sure you’ll get there :)
Title: Re: Suspected centre diff bolt failure LT95
Post by: Hufav on May 16, 2018, 09:13:27 AM
Got it apart to find the rear tapered roller bearing on the centre diff had let go. It has destroyed the rear housing. Everything else thankfully looks OK although I haven't got the I haven't got the intermediate shaft (or centre diff) out yet as the intermediate shaft is jammed in for some reason. I'm thinking it's stuck on what looks like locater dowels at either end of the shaft. If some has a suggestion I'd very grateful 
One other observation was there was damage to the pto housing from the chain rubbing against it below the sprocket. I guess a new chain might remedy that but I find that a bit of a worry in terms of alloy shavings floating around. Is this common?
Plan is all new bearings. Send the shafts to a shop to have the bearings installed and preloaded. Obviously replace rear housing.
Title: Re: Suspected centre diff bolt failure LT95
Post by: STDDIVER on May 16, 2018, 11:20:23 AM
The auctions are on at the moment - Gray's might be an option for you for a replacement - might be cheaper - or not?

STDDIVER
Title: Re: Suspected centre diff bolt failure LT95
Post by: Hufav on May 16, 2018, 07:09:02 PM
Yes I did consider the auction and had a look at Minto. There two boxes available. It's a raffle though and you could be buying problems. At least I know what I have here. It's a very smooth transmission so with the transfer case rebuilt I'm hoping for a bit of longevity. I appreciate your input though. Thanks for that. Cheers Hugh
Title: Re: Suspected centre diff bolt failure LT95
Post by: BEARMAN on May 16, 2018, 07:54:11 PM
Give me a call mate.
Title: Re: Suspected centre diff bolt failure LT95
Post by: Carzee on March 03, 2019, 05:23:32 PM
I am posting here a comment made by Bearman elsewhere which is "gold".

"Bearman re LT95A. 10feb2019

"Lots of LT95's have been assembled without the loctite on the centre diff bolts and a couple of other gears in the transfer case and subsequently lead to failure, in some cases completely destroying the casing. A relatively simple job to do especially on assembly. "

Also..

"The oil migration from the transfer to the gearbox is a result of the distance sleeve and gear on the end of the mainshaft NOT being loctited onto the shaft. You will most likely find your seal is still in good condition and what causes it is the distance sleeve is not loctited and because of the friction of it inside the seal it wont turn with the shaft and remains stationary with the shaft turning inside it. It has 2 holes for a puller and oil splashes inside the sleeve and the shaft splines act like a vane pump and pressurise inside between the shaft and the sleeve and when the oil is hot and thin it can migrate inside the distance sleeve to the gearbox. You can fix it by removing the gear and sleeve from the end of the mainshaft (in Situ) and loctiting them both onto the shaft.

"However before you remove them it is vitally important that you put the gearbox into 3rd gear (which stops the mainshaft from moving while you have the end bits off) otherwise you will have major dramas trying to get them back on.

"While you are at it bang a 30mm brass welsh plug into the reverse idler shaft hole inside the transfer case. This is another oil migration area but from the gearbox to transfer.

Which Locktite?

"Use 609 on the distance sleeve and 648 on the input gear and also on the small hi range gear on the centre diff. Use 277 on the centre diff bolts (both casing bolts and low range gear bolts)."

Thank you Bearman for your numerous posts with such experienced information, its very much appreciated by myself and others to come down the same track in the future.
Title: Re: Suspected centre diff bolt failure LT95
Post by: BEARMAN on March 03, 2019, 09:12:00 PM
No problem. Pleased to be able to help.
Title: Re: Suspected centre diff bolt failure LT95
Post by: Hufav on August 09, 2019, 02:28:40 PM
I haven't been on the blog for some time due to one of life's curve balls but I could not agree more with you Carzee. Bearman, apart from his encyclopedic knowledge on all things Lt95, is one of life's true gentlemen. He was extremely generous with his time and expertise in getting me back on the road. Thanks very much Bearman!