What are the JCB 3CX Varients and a basic Operators guide?

[agrimax]

Isn't there a transmission dump button on the front loader control lever? Would expect there to be one on the gear lever as well,but just looked on the parts list and it would appear not.... Must have to flick the shuttle lever into neutral for every gear change then?
Your serial number comes up as a 3cx 2wd Sitemaster USA.However as you're in the UK,that serial number range is also covered by the 3D range. So even though the decals may say 3CX it may actually be a 3D.I think a 3CX sitemaster and a 3D are pretty much the same thing anyway!!

[Slooby]

My manual specs iso 15 for the brakes. (P7 3cx)
32 will work, but it won't flow as fast, so the brakes will feel less responsive.

For the Slew Gearbox, it's slow moving with straight cut gears, so not very demanding of the oil (I don't think it needs to be an EP grade)
90W is good, 80W-90 or 85w-140 is fine too.
Be aware the slew box collects water that needs to be drained or the water will displace the oil. The oil will leak out leaving water in the bottom.

Handy to know, thanks Ian

I'll amend my original post accordingly as I thought it would be useful to capture everything in one place for people searching for the equivalents to the JCB branded lubricants in the future.

I had seen that checking for water in the slew box was on the daily checks in the Workshop Manual. Do you have the operators manual then? Because I think there would be a lot of people who would love to see it scanned and put in the downloads section here!

I'm curious as to why JCB decided on EP90 GL5 for their 'HD90' oil, I wonder if they went down that route because the 3CX could be fitted with a breaker on the backactor, so could impart more load on the Slew gearbox?

Back in my Impreza tuning era I had a hybrid 5 speed gearbox that used billet straight cut gears for 1st and 2nd, and then billet helical cut gears for 3rd and 4th, with the stock helical 5th, I used 85W140 in that 'box and even it couldn't cope with the power delivery of my loopy 2.5 litre 4 pot and huge hybrid Garrett turbo, the torque delivery was so brutal that the oil was being squeezed out off 2nd gear cluster and spalling metal off the sides of those straight cut gear teeth! That was always the problemwith the 5 speed as the gears were only 10mm wide on the stock 'box, and they eeked them out to 11mm on the billet 'boxes by removing a baulk ring from the cluster, the later stock Sti 6 speeds had 25mm wide gears as I recall, and were nigh on bomb proof as a result.

[Slooby]

Isn't there a transmission dump button on the front loader control lever?

I suspect that could be the button I have ringed in this pic:



What is the purpose of the transmission dump anyway, does it act like a clutch pedal to disengage drive while using the bucket to shunt stuff around?

Must have to flick the shuttle lever into neutral for every gear change then?

Umm, that could be important to know!

Your serial number comes up as a 3cx 2wd Sitemaster USA. However as you're in the UK, that serial number range is also covered by the 3D range. So even though the decals may say 3CX it may actually be a 3D. I think a 3CX sitemaster and a 3D are pretty much the same thing anyway!!

Interesting, well it has got 3CX decals and you can see where it once had the Sitemaster ones (which I suspect got blown off when the dealer steam cleaned her), maybe it was a cancelled US order, or one that got re-allocated. What was a 3D then and could they also be had with the 'Extradig' extending backactor boom?



I suspect she is still in what's left of her original paint, she spent most of her life on a farm and got parked up in a tractor shed, so the cab is remarkably rot free, and the paint just rubbed off from use...hence my interest in the Tractol paint products

[Slooby]

Slightly odd place to find a bit of a 3CX lineage, but...

https://toyota-club.net/files/faq/15-11-01_jcb_eng.htm

[gecko.cx]

Do you have the operators manual then? Because I think there would be a lot of people who would love to see it scanned and put in the downloads section here!

Hi Slooby, Yep - Downloads -> Earthmoving Equipment -> JCB -> Page 3 (I uploaded it a few months ago)
http://www.classicmachinery.net/forum/app.php/dl_ext/?cat=5&sort_by=0&order=ASC&start=3
This Operators Manual suits mine, not yours, but much will be common. Keep looking for the correct manual, but this will help.

I'm curious as to why JCB decided on EP90 GL5 for their 'HD90' oil, I wonder if they went down that route because the 3CX could be fitted with a breaker on the backactor, so could impart more load on the Slew gearbox?

I'm not sure what constitutes an "HD" oil, but I'm pretty sure it isn't equivalent to an "EP" oil.
My P7 is 4x4 and is spec'd for HD 90 in the front diff & hubs- I suspect that's the reason.
There are no hypoid gears, so EP oil isn't required (I suspect the "HD" oils cope better with shock loads)

[Slooby]

Thanks again Ian!

Having downloaded you Operators Manual and taken a quick sqiz at it, it's clearly for a quite different machine, but as you say there are similarities in the basics, so it's a good starting point at least.

As for the HD90/EP90 ponderings I'll do a bit more research, would be handy if I ended up choosing the same oil as all the Landies in my collection need for their differentials though

[Slooby]

Ok, I've done a bit more research into the differences between SAE 90 (which is similar to 85W90) and E90 GL4 and EP90 GL5

As I have understood it so far:

SAE90 is a moderate weight gearbox oil
EP90 GL4 is a differential oil with more additives in it to stop it taking on water (I've seen SAE90 come out looking like milk from a diff casing), deal with Extreme Pressures, cling to gear teeth better and stop what I would call 'galling' of the wear surfaces.
EP90 GL5 has nearly DOUBLE the EP additives in it over GL4 and is better able to deal with shock loads.

Neither EP grades should be used in a situation where it can come into contact with copper or bronze parts as the main additives are Sulphur and Phosphorus which attack and break them down.

So it sounds like EP90 GL4 should be ok in the Slew gearbox, assuming it has no bronze bushes or oilite bearings in there! [Scurries off to look in the Service Manual:- nope, no bronze bushes or oilite bearings in there]

[gecko.cx]

Sure - no problem. Certainly interchangeable with gear box /transfer case oil. Off hand, I can't remember what I put in my 2a difs.

[Slooby]

Off hand, I can't remember what I put in my 2a difs.

SAE90 hypoid has been the norm on the various Landies I've worked on over the years, stinks like cat piss

[Slooby]

For the Impreza gearbox and rear diff, if you did a lot of track work, or had gone as mad as I did on the tuning, we used 85W140 in both, however, if you had a plated LSD in the rear you used 85W140BM in the rear diff alone as the additives in that were specifically formulated to work with the clutch plates in that type of diff. You couldn't use that variant in any other type of LSD (viscous or ATB) application as it would cause more wear and slippage issues