Rocky Gearbox

[foster_the_fat]

Are the Petrol and Diesel G/Boxes (for Rocky) interchangeable? For instance I have a F85 (1987) petrol, would a similar year diesel G/Box fit?

Has anyone got much more that 300k out of a rocky G/Box? Mine is starting to whine noticibly in 4th and 5th.

Cheers.

[RockyF75]

I sincerely doubt it, but could be wrong. 300k sounds like a good life if you havent done anything to it. I've had nothing but trouble with mine, and just spent ~1hr driving @ 40kph limping it to the mechanics, as something went BOOM in the T-Case

[foster_the_fat]

The 3y has no power and stuff all torque, so no breakage....

[tabrocky]

Mine has had a whine in 4th and 5th for the last 100,000km

It's done 315,000k now. I rebuilt it at 220,000k. Didn't get rid of the whine despite replacing all bearings, etc. I just live with it (turn the stereo up). The N/A DL motor isn't exactly a powerhouse either.
Iv'e found them to be a pretty reliable box providing there not abused.
I'd probably recommend doing bearings and things every 200,000km regardless. There not really a hard box to work on and you can source the bearings at any decent bearing shop.

As for interchageble, I would probably think yes but i'm not speaking from experience here. I thought the ratios were all the same, the only difference was the diff ratio's.

Bundy might be able to help you out here.

Cheers.

[RockyF75]

Hmm, tab, when u say rebuilt the Gbox, do you mean just the box or box and Tcase? Cause i've had all the bearings in my box done adn the synchros', and 2nd gear i think. But the Tcase only had the bearings replaced. But then ever since, its still had that 'whine'. I just assumed it was a noisey box. So now some gears or sumthing in my Tcase have gone kablewy i'm thinking the whining was from there? Worn gears or sumthing?

If ur in sydney foster_fat i know a mechanic thats got very reasonable prices and has done alot of work on rocky G'boxes - MINE - Pm me if you want his number.

[murcod]

It's not a diff or uni-joint noise is it?

[tabrocky]

Box and Tcase RockyF70.
My whine mainly seems to be in 4th and 5th gear so that rules out the diff and uni's. Besides the uni's are near new anyway.
Most common problem I know of is loosing the nut on the end of the shafts. When I do the box in my new rocky I think i'll dab a bit of weld on them, just to make sure they don't come undone.
The only real design fault i know of so to speak is the use of needle roller bearings on some gears where it would have been better to use a bush (strange as that may seem). It's complex to explain so i'll leave it out unless you really want to know, however it can be the cause of an audible whine.
It is common for these boxes to be a bit noisey with a few k's on them. Infact i've only ever heard of one quiet one.... or should that be didn't hear??

Good luck with the repair. Are you sure you didn't get any water in there with all that playing at stockton??

Cheers.

[RockyF75]

Good luck with the repair. Are you sure you didn't get any water in there with all that playing at stockton??

Cheers.

Was my first thought, but i stuck my finger in box and the oil is all nice and creamy yellow . Not the usuall milky white of water + oil (i've seen it too many times )... if i did and i missed it dw, my mechanic will verbally beat me. I think he's more sick of my car breaking than me

[murcod]

For noise issues put some Redline gearbox oil in it.

[tabrocky]

For noise issues put some Redline gearbox oil in it.

Who makes that? Where do you get it?
Is this some form of slick50 for gearboxes?
I just use castrol in mine. It's a strange oil. Almost clear to look at, not the normal yellow.

Cheers.

[BundyRumandCoke]

I actually dont know about the interchangability of the petrol/diesel gearboxes. I do know from experience that rebuilding gearboxes from a fairly poor condition doesnt remove whines completely. The gears wear against each other with the wearing of the bearings. When you replace the bearings, they wear on different parts of the gears, and sometimes a less worn part is running on a more worn part hence the whine. I had a similar problem when I broke a couple of teeth on one gear. Replaced that gear only, and could never get rid of the whine made by a new gear running on a worn one.

Try the Redline oil, from all reports its good stuff.

[HotFourOk]

For noise issues put some Redline gearbox oil in it.

Who makes that? Where do you get it?
Is this some form of slick50 for gearboxes?
I just use castrol in mine. It's a strange oil. Almost clear to look at, not the normal yellow.

Cheers.

It is a shockproof gear oil, which is quite expensive, although it works very well.
http://www.redlineoil.com.au/product-in ... p#gearoils

A cheaper alternative is Nulon Gearbox and Diff treatment.. you add a tube to your gearbox oil and it removes noises, most of the time.
If you add new oil and a tube of this, it will help to alleviate the problem.
Available at parts retailers.. eg supercheap, for around $20.

My Corolla Seca would crunch at high revs going from 1st to 2nd gear, no matter how you shifted it... I changed the oil to Penrite.. and it has neva done it since

[tabrocky]

Thanks for that HotFourOk.
If it gets any noisier i might have to look into this. For now the stereo has a few more watts to eleviate the problem.

Cheers.

[foster_the_fat]

Glad to hear they are a noisey box generally, cause mine whines in a few gears. When it is idling I can hear the box turning over, put the clutch in and it stops, so I assume it is the box. Shifts ok, very hard to get into 5th. Think I will look at getting the bearings done in the near future.

[murcod]

Change the oil to Redline- it's worth the money. I've tried Nulon in the past and it hasn't worked for me; have also tried Castrol VMX80 (made for shift problems) with no luck.

Mine's in getting a rebuild now after 3 years of using Redline- and not because anything failed, I just finally decided to get it done.

[RockyF75]

Change the oil to Redline- it's worth the money. I've tried Nulon in the past and it hasn't worked for me; have also tried Castrol VMX80 (made for shift problems) with no luck.

Mine's in getting a rebuild now after 3 years of using Redline- and not because anything failed, I just finally decided to get it done.

Slightly offtopic, but when someone says 'rebuild'.. what exactly gets done? Is it just all the bearings, or bearings AND gears?? and can i ask roughly how much its gunna cost?

[foster_the_fat]

I will try redline oil. Just changed to VMX 80 and it made no difference.

I am also interested to know what a 'rebuild' would cost? I would guess between $1000 and $2000.

[murcod]

It all depends what's wrong with the box. I'm getting all new bearings and synchros on second and third. I'm also getting the clutch done at the same time & bearings in the transfer case as well..... I'm expecting a bill around $1500.... It's getting done through a friend so I'm also getting a discount.

The stupid part is I'm then looking at selling it.... But I couldn't sell it with the box as noisy as it was and dont want to do a half arsed job either and hand on problems to a potential buyer.

So, if anyone is after a Feroza in very good condition- excellent for the age- and with lots of gear replaced / rebuilt over the last three years, contact me!!!

You're better off putting something like Redline in before you've got an issue, but as I discovered it can make a worn box usuable for a long period of time. I'll be running it in all my future vehicles.

[tabrocky]

When I did the box in my '86 F75 it cost around $1200 including new clutch, pressure plate, gasket kit, syncro's, bearings, needle bearings, seals and some spring clips and other assorted bits and stuff. All the labour was done by me so no cost there.
Took me one long weekend to pull it out, strip it and clean it. Then another weekend to put it back together and fit it.

Rebuild basically means to do the above. Gears are generally not replaced unless they have serious wear on them or are damaged.
Like already mentioned, you can often get noise from gears wearing slightly differently due to fitment of new bearings changing there alignment slightly.

The thing is, once you have done the bearings, and assuming you have done it all correctly, there isn't much else to go wrong. Even if you still have a noise after, you know it's not from the bearings. Gear noise is exactly what it says... "Noise". It doesn't mean the box is going to blow.
Anyone hear ever driven a Landrover defender?....
Noise (vibration) can prematurely wear bearings but it would have to be fairly severe and again you would hear it getting worse and worse.
If you overload the box, get water in it or run it dry then you can damage gears etc, but generally they'll just keep going but get noisier and noisier thats all.

Hope this helps.
Cheers.

[BundyRumandCoke]

A complete rebuild, bearings AND gears would be rediculously expensive. The gear I mentioned above, about 6 years ago, cost me $350, thats one gear. One set of synchro rings and pins cost me over $100 about 4 years ago.
A rebuild is normally only bearings, and maybe synchro rings, which also wear. Cost of bearings would run to about $4-500 dollars. The bearings are all readily available through places like CBC or SKF, there are no special bearings in either gearbox or transfer case, unlike things like steering columns or power steering pumps. They are fun to buy for.

[foster_the_fat]

Thanks for the info. It sounds as though it is wise to rebuild at some stage before things actually break. Cheers

[murcod]

The bearings are all readily available through places like CBC or SKF, there are no special bearings in either gearbox or transfer case

Well, for Feroza there would appear to be. A couple of the bearings for my box are ~$200 ea ex Japan, luckily they're the ones with no wear!

I'm now up for FOUR synchros (they were all stuffed) plus the bearings, fly wheel machining, synchro springs etc. The mechanic when he test drove it reckoned all the synchros were fine, but it was a different story once he stripped it down. Goes to show how well that Redline oil works!

A heavy duty clutch is only an extra $20 - with a heavier clamping force pressure plate - so that's money well spent.