Jump to content

changing gearbox oil frequency ?


Recommended Posts

It does last well though...

For a variety of shameful reasons mine hasn't been changed in... shall we say 'a time period longer than that', and there has been no noticeable change from the gearbox. I guess it doesn't degrade in the same way that engine oil does with all the combustion effects etc.

Cue gearbox explosion tomorrow morning now I've said that!

Link to comment
Share on other sites

I am definitely getting a tapping noise from my gearbox, although gear changes are still okay and no noticeable difference in performance just this annoying tappet sound coming from the transmission.

When I had the gearbox recon done about 15 month ago, I got the transmission specialist to put LR spec oil in. Driving afterwards I was struggling to get second gear until the oil warmed up so took it back. He suggested the grade of oil I supplied was too viscous so recommended an alternative.

He put in standard automatic gearbox oil in (Which is what he uses on all the gearboxes he overhauls) and hey presto problem was solved.

Wondering if now the new synchro's and gears have now bedded in and if its now worth reverting back to the LR specified oil grade ?

Fortunately I kept the spec oil when he switched it over, so can change it back.

Link to comment
Share on other sites

16 hours ago, IanT90 said:

I am definitely getting a tapping noise from my gearbox, although gear changes are still okay and no noticeable difference in performance just this annoying tappet sound coming from the transmission.

When I had the gearbox recon done about 15 month ago, I got the transmission specialist to put LR spec oil in. Driving afterwards I was struggling to get second gear until the oil warmed up so took it back. He suggested the grade of oil I supplied was too viscous so recommended an alternative.

He put in standard automatic gearbox oil in (Which is what he uses on all the gearboxes he overhauls) and hey presto problem was solved.

Wondering if now the new synchro's and gears have now bedded in and if its now worth reverting back to the LR specified oil grade ?

Fortunately I kept the spec oil when he switched it over, so can change it back.

I have seen Defenders with EP90 in the gear box because the "specialist" thought it was standard LR spec oil.  It is standard spec for the axles and LT230, and for the whole transmission in Series LRs, but was never correct for LT77s or R380s (and possibly not for LT85, though I don't know about that one).  The point is that any "specialist" who refers to "LR spec oil" instead of EP90, W75, ATF DIII, MTF 94 and such is not a specialist at all but a bodger.

Link to comment
Share on other sites

Firstly I have definitely got EP90 in the transfer and originally had MTF 94 in the gearbox. However that appeared initially to be bit to viscous and struggled getting second till the oil warmed up. The grade put in the gearbox after I am not sure about but sure but think it was ATF ? did cure the the gear change issues though.

The tapping is only when moving and is audible through the transmission tunnel, that's why assumed gearbox. However, I could be mistaken never considered universal joint on the prop shaft ?

Thought the noise was from the engine originally noisey tappets, but when I had the bonnet up the engine actually sounds quite sweet considering its age. That's when I started looking else where for the problem.

I kept the MTF 94 oil when it was taken out, so can replace the oil that's in and see if that makes a difference.

As for the Prop shaft, I don't have a decent press or garage to work in so replacing universal joints is out. Probably just replace with new starting with the front, whats the difference with heavy duty wide angle versus standard ?

Ian

Link to comment
Share on other sites

That's an expensive way to replace UJs! You could do it with a 9 /16 spanner to remove the prop and a g clamp and socket to push the new uj home if you really had no facilities. 

 

Doesnt sound like the release bearing if it does if when driving really. It'd do it at idle if it was that and dissappear when you dip the clutch. 

Link to comment
Share on other sites

TBH not a total loss I am not planning to get rid of the old girl, so would overhaul the old prop at my leisure then have a spare ?

As for release bearing had that on my old clutch assembly before it was changed, so kinda know what that sounds like and fairly sure that's not the cause !

This is more like a distinct tapping rather than a rattle and only when under load not really noticeable if I coast with clutch down or idle at lights.

Definitely worse at start up just setting off, after about 3 miles it starts to reduce in amplitude and it becomes less prominent after driving for a while, although still there in the background.. .

Link to comment
Share on other sites

That's interesting I adjusted the hand brake travel not to long ago (June as it was an MOT fail), wonder if that its linked ?

Not sure if I have carried out the adjustment correctly, tightened was adjuster until no movement then backed off until pads just catching the the drum.

The handle adjustment is now about 3 to 4 notches, which is about right.

Don't know what else I needed to do ?

Link to comment
Share on other sites

It sounds right. I'm just throwing some cheap ideas out there before someone says drop the gearbox! Worth checking the handbrake isn't sticking/catching though.

I doubt changing the oil (as you mentioned earlier) will have any effect.

Have you checked the UJs for play?

Link to comment
Share on other sites

An overadjusted hand brake can make horrifying bangs and thumps, so back it off just a tad and then test drive.

I used to replace UJs with a rubber mallet and two sockets (one with an internal diameter larger than the bearing cups to support the yolks, and one with an external diameter similar tot he cups for use as a drift).  You have to be careful not to drop a roller, but it's manageable.  The vice did make it much easier when I got it, but it's not essential.

Link to comment
Share on other sites

Sorry I have not replied sooner been off work for couple of days and wife had me doing jobs on the house.

So i have not had a chance to check the UJS  yet. However, convinced now it's from the transmission. When driving it's noticeable tapping noise when I dip the clutch it goes, starts off more noisey but gets progressively quieter as I drive but never completely disappears. Also noticed gears are starting to become a bit stiff again when I first start off and as with the oil change they get easier the further I drive.

Fairly certain I don't have a leak from the gear box would have noticed losing that much oil on my drive etc but low oil could be a possible cause need to drain the box asap and re-fill with my back up oil.

Firstly if it was the UJS don't think it would impact the gear changes when gearbox is cold and improve with journey's same with the noise, but I will keep my fingers crossed it is something that simple.

How much play would you expect from a union joint in relatively good condition ? 

In mean time I will back off the hand brake a notch, change the gearbox oil then check the UJS.

 

Link to comment
Share on other sites

A good UJ has no play at all (check rotationally and laterally - the plastic thrust bushes inside the bearing cups can crush or disintegrate, allowing the spider to slide in and out of the cup).  A UJ can also bind in specific spots, which causes vibration and forces on the bearings of the assembly adjacent to the UJ (box or diff).  You can only check properly by removing the prop and exercising the joint in every direction, both unloaded and with torque applied in each direction (this will help detect grooves worn into the spider ends by dry bearing needles in the cups).

Link to comment
Share on other sites

Cheers for that will add to my list, planning to top up the transfer and diffs with oil first see what impact that has. If no impact on noise will change the gearbox oil see if that has an impact.

Next job when I eventually get a day off work (some time in March), I plan to replace both front and back diff flanges and oil seals as both are leaking (So can check the UJ's then).

Next job is to track down the leak on the transfer box (if I can find it ?).

I then need to replace my brake vacuum pump leaking oil all over the engine.

Finally I will take a look at refurbishing the UJ's.

Cheers for the info.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy