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  #1  
Old September 11th, 2014, 01:53 AM
RBBailey
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LT85 Questions

Unless I'm wrong, I've got an Lt85 in the 110.

What should I know about this gearbox? Proper oil to use? Problems to keep an eye out for? etc....?

I'm planning on eventually swapping to a 4.2, at that point I will be open to swapping gearboxes as well, but it's just not something that is happening unless it falls in my lap.
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Old September 11th, 2014, 06:58 AM
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http://lrs3turbo.4800bps.com/docs/LT...arbox_info.pdf
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Old September 11th, 2014, 06:59 AM
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I have an LT-85. I think LR recommended 20W50 for use in it but that is just me throwing that out from random memory. I think this transmission is awesome. I don't shift fast. It feels like it has much longer throw than the other LR transmissions in my opinion. There are two types, split case and solid. This bit is straight from Ashcroft's website.

Quote:
Originally Posted by Ashcroft Website
Whilst the LT85 is renown as a very strong gearbox, they are prone to two problems; premature wear of the 1-2 selector fork and premature wear in the 5 main bearings, this is due to the fact that the LT85 has helical gears which produce end thrust but the bearings are all ball bearings as opposed to taper roller bearings.
Some customers upgrade to the R 380 instead of fitting another LT85. The suffix L R380 is similar in strength but is smoother to use and should last longer. A different diff lock linkage and hi/lo casting is required also you will need to trim a small section out of the seatbox but nothing too drastic
Watch out for it leaking? haha
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Old September 11th, 2014, 08:48 AM
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The main bearings can and will get noisy at a low mileage because they are old school non-tapered roller bearings. This means they don't take thrust loads very well. However its not indicative of a problem with the gearbox, just be aware that when you start hearing bearing noise it's to be expected.
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Old September 11th, 2014, 09:32 AM
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Lt85 have roller bearings not tapered roller bearings . Because they aren't tapered is why they have an issue taking the side loads created by the type of gears used. Wheel bearings would be an example of a tapered bearing, they take side loads well. Rovers engineers didn't account for the side loads that the helical gears would create. That said lt95's and 85's were much stronger robust gearbox's than the Lt77 and R380. They just have a more agrarian feel with lots of throw and huge shift gates when compared to the lt77 and r380.

I know the 4spd Lt95 used motor oil but not sure about the later 85. Ask Dave Ashcroft what he suggests.
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Old September 11th, 2014, 09:35 AM
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i think he said they were not tapered.

------ Follow up post added September 11th, 2014 06:35 AM ------
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Old September 11th, 2014, 04:10 PM
RBBailey
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OK, thanks for responses.

Based on what Uncle says, if I'm experiencing "slack" while shifting -- sort of like when you have to drive your Disco around with one prop shaft pulled out -- while letting the clutch out, this is "normal" for this gearbox? (Especially in 1st and 2nd.)

And I'll see if I can do the research for the right fluid.

And what about a hint of grind going into 2nd and 3rd. It doesn't happen all the time, but if I'm sort of absentmindedly progressing through without trying to be more careful, it gives a bit of feedback when pushing the lever into 3rd -- is this a synco problem developing?

It may be good to know that I really have a quick clutch. That is, when letting it out it really has no in-between. The clutch is on or off, even if I try to bring the pedal back real slow.

Pretty ignorant of gearing and clutch issues, so forgive me for the base questions.
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