Hard to select 2nd gear when cold d1 ok hot

First thing in the morning when cold 2nd gear can be very hard to get- I haven't checked the oil level yet and as this mtf 94 is not easy to get is the diff lock stuff worth the extra money-there sales blurb suggests it sorts this problem.Once the box is warm all gears are really easy r380 box.Anyone any experience with the diff lock stuff?

seems to be a common disco thing, my td5 is eggzackley the same

Thanks for that Nigel-I guess I will just live with it (will check oil level though)but it is bastard first thing and don't want to wreck anything

I also think it's worth an oil change. Try refilling with new MTF 94.

There was a issue where 2nd gear was a problem, and LR released an advisory to use MTF 94. Made mine better...

Here's the supporting info I found:

Gearboxes

Having covered engines, we can now consider transmissions.

5-speed LT77 and R380 main gearbox (Land Rover 90 & 110, Discovery, Range Rover)

Firstly, let’s deal with the somewhat notorious LT77 and R380 5-speed main gearbox. These are famed for a poor, notchy gear change, especially from 1st to 2nd gear.

The notchy gear change is due to a combination of a weak synchromesh and the use of a plain mineral ATF fluid.

ATF was originally specified for the LT77 5-speed gearbox and, theoretically, could be used in the later R380 box. Type DIII is the best grade currently available. ATF was originally specified because of the weak synchromesh in the LT77 and R380 boxes (especially second gear).

ATF has a very low viscosity (rated as 5W20 since it falls below normal gear oil viscosity grades) and so it has minimal drag on the gears, enabling the weak synchromesh to do the best of a bad job.

BUT ATF has several drawbacks which is why it is NO LONGER recommended for use in such boxes. These are:

It is generally a plain mineral base stock formulation (even DIII) and this, coupled to its very low viscosity, means that it is poor at preventing metal to metal wear in manual transmissions.

This is compounded by the fact that the viscosity improvers within (thickeners) are more rapidly sheared down in manual transmissions. Again, this reduces the protective film strength of the ATF in those areas of high pressure contact and also increases transmission noise.

ATF thickens as temperatures drop (increasing that drag on the gears) which is why folks notice that gear changes are worst on cold mornings and improve after a few miles motoring when the ATF has warmed up a little.

...
Land Rover currently has commercial arrangement with Texaco/Chevron that leads it to recommend a Texaco/Chevron MTF94 fluid. From the freeback we have received and read on this Forum and elsewhere, we feel it’s a little too viscous (5W30 or 70W80) to give the best results. Nonetheless you should use it in preference to ATF if your choice is limited to the two.

However, there are better alternatives such as the fully synthetic MT75D gear oil we have developed. Rather than simply plug our MT75D I’ll give pointers to what you should look for when seeking alternatives to ATF or MTF94.

Firstly, the lubricant must have the original 5W20 low viscosity of ATF fluids to give minimum gear drag. However, it MUST also be formulated only from fully synthetic base stocks since these will have a much higher lubricant film strength so as not to be squeezed out of those all important high pressure contact areas where wear might occur. This, and the low viscosity, has the added benefit of reducing friction which lowers transmission noise and improves economy.

It must also be highly shear stable and able to maintain its optimum working viscosity over a very wide temperature range. This and a very, very carefully matched coefficient of friction (probably the most critical parameter) will ensure that it dramatically improves gear shifting in LT77 and R380 boxes (especially from cold).

It is the improved shear stability and higher film strength that enables synthetic gear lubricants to outlast their plain mineral counterparts by up to 5 times. However, we err very much on the cautious side and recommend only a doubling of drain intervals.

Note that unlike engine oils, gear oils do not have combustion by-products building up in them, nor do they suffer the higher temperatures of engines, so extending drain intervals is entirely acceptable if the lubricant is of the highest performance and the increase is modest. The exception to this would be if the gear oil were contaminated, perhaps by water or mud during deep wading, though this is unlikely. If the oil is contaminated in this way it MUST be changed immediately, regardless of its formulation.

I use cheap ATF in my R380 and change it every 3k, never have any problem.