For 2 people is Engel 60 ltr or 40 ltr best.

Paul : please tell us what an extended trip means! for some its a 4 day weekend, for others its 3 weeks on the Canning Stock Route !! Sorry but none of us are mind readers and daft questions generally get daft answers !
steve

A more helpful reply might go along the lines of 'It all depends on what you want to keep cold'. If you start off with lots of fresh vegioes, milk, bread, meat and need a dozen coldies a night you might need the 60. Same if catering for a family. But after a week on any trip you'll probably have used the fresh stuff and will be into powdered milk and fresh damper with lots of space in your fridge.
I've never needed anything bigger than a 40 for up to three people.
Joihn R.

Paul
My wife and I have a 60 Litre Engel that serves us well. We have never been able to determine whether it was necessary to go the 60 litre over 40 as there are pitfalls attached. One is the extra power draw but to date that hasn't really been a problem. The 60 Litre is heavy and awkward which is my main concern, not so much now but as I get older.
We do however manage to fill the fridge every time but sometimes only with what could be deemed "luxury" items (red wine, cheeses etc). Your answer will come from the length of your trips. We are just about to set out on 5 weeks thru Gibb River/Kalumburu so I'm sure will appreciate having the xtra capacity then.
None of that will help you and I think you will always be faced with the question every time you go somewhere.
Cheers

Paul, we have a 40lt which has done a good job. The system you use, is just as important. For example, on trips of a few days, we just use it as a fridge. But on longer trips, we use it as a freezer. We put in meat, sausages, etc, and also those thermo ice cubes, that are refreezable. Then the day before, we select the items we want for thawing, put it in the esky, with the thermo ice cubes, and presto, we've got thawed meat or whatever, each evening, as well as some cold drinks.

We went for the 68 litre EvaKool and we always manage to fill it even for short trips - probably not with essentials, but it's certainly nice to have the space (especially with a couple of kids). We went for the EvaKool because it is very light compared to other fridges and it has 40mm insulation all around and is white and will reflect heat better.

On the last long weekend we went out to the Gulf country in Far North Queensland (hot days, cool nights) and ran the fridge for 56 hours without starting the car. The 90 Ah battery went from fully charged to 11.5 volts in that time.

Paul : have you thought that a 40litre for general cooling and a second one of say 30 litres for frozen/cryovac packed meats might be the way to go for an extended trip ?

Seeing as you have the sliding shelf, both would fit on and you could dispose of one at the end of the trip ...

Paul, we use a system similar to JohnF. We have 40L Engel, 40L esky (with good quality insulation) and 4 freezer blocks (each block is twice the size of your regular freezer block). We run the Engel as a freezer and fill with frozen meat and two of the blocks. The esky has everything else and the other two blocks. The Daily routine is 1) Morning (a) Swap blocks: eskyfreezer and (b) Move frozen meat freezer-->esky to thaw for dinner 2) 3.00PM: Put cans of (warm) beer in the Freezer (enough for that night) 3) Evening: Drink beer; Eat meat. Advantages: No need to buy ice for esky. No water in esky. Freezer is opened only twice each day. No chrio-packing. Last year the 40L Engel carried all the meat for 2 people for 4 weeks (still had frozen meat left over). For you this would mean putting your esky on the fridge slide rather than the Engel because you are in and out of the esky all the time. I am interested in JohnF's idea about using the mesh instead of blocks - I will give it a try. I wonder if the water in the mesh would be absorbed by any porous items it might touch in the esky (eg paper bag, or deli meat wrapped in paper. I suspect the blocks would take longer to thaw out. We find the spent blocks are still partly frozen each morning. Good luck.