80 Series Gearbox Problems

sounds normal to me. chucked castrol vmx-m and made no difference

There is an oil called redline shock proof light that is very good for this specific problem, it is a full synthetic ester oil.
I am a mechanic and have used this oil in many gearboxes including cruisers for this problem with nearly always a total fix.
It will take about three days to start to work.
The only draw back is that it is about $130 for one US gallon (3.78lts).
First you may want to check you have correct clutch operation and no spigot bearing drag.

I don't know what specs your Lubrimaxx gear oil is. And I'm guessing you've got a H150F gearbox. But anyway, I have the same box in the 79series - Used the Castrol VMX-M 75/85 at the last change and its the best I've used for the cold changes - just marginally better than the Valvoline Duragear I have been using.

The other cause of difficult gear change is that the clutch is not fully releasing. Given that its not adjustable, any chance that you have air in the clutch fluid? May be worth bleeding it.

All, and I mean all of the 80 and 100 series that we have run over the years eventually (around high mileage levels) develop a pretty severe baulking of 1st and 2nd - usually second worse? I havent tried different oils so cannot comment, but it seems to be that "they all do that" and requires a bit of juggling engine revs for a decent shift. Of course eventually the gearbox needs overhauled.
Gil

Dan....I had to replace my r151f g/box in my troopy and a brand new genuine toyoa g/box with bell housing and a 20k waranty...$3300....don't waste your money buying second hand. I also needed a new intermediate shaft cost $350....while it was out I replaced the rear main seal and the clutch...transfer box was all good....regards Phil

Hey Dan,

A couple of guys on the 80 Series forum are talking about the same topic - if you want to have a look go to www.offroad80s.com

Karl

Give the 'box a dose of Nulon- worked for me !!

Hi,have used penrite lite oil in a 73 and 80 series 5speeds and all cold shift problems gone.i am not a penrite fan at all but that was the only oil out of about 5 diffferent ones i tried that actually worked.cheers Paul

Not sure if yours is the 94 model?
If it is Toyota had an issue with this gearbox doing just that.

I had one and it had 100.00klm warranty on it so they rectified the problem free of charge.

Bot cause a lot of other issues whilst doing the changes.
Like no oil seal between the gearbox / transfer box [twice]

ordered the wrong parts.

Left a block of wood on top of the diff housing to support the engine that in turn dropped over and onto the steering.
Not nice driving down Mt Tambourine with tonne behind you and no right hand steering.

Then to top it off the mechanic smashed the drivers side wheel arch into the hoist.

Service managers comment, you should look at getting a Pajero.

Well done Tweed Toyota.