Most are made in India except the last two models in the series are made in Agusta Georgia This year the 5003 series will be avaliable in 4wd (2008 models). as well as the standard 2wd t6hey have made for several years now.

Having a basic engine "platform" or mold is one way for OEMs to minimize costs while still being able to accommodate the customer wanting a product in a specific horsepower rating and/or price range. The premise is to cast the basic engine block and cylinder head(s) so that they are "robust" enough to support an engine at the "maximum rated output" for the design and mass of the engine. After that, lower horsepower versions can be developed by changing things such as the injectors and injection pump, and pistons (just because the specs show the bore to be the same does not mean the pistons are identical). Each horsepower version will produce it's own specific amount of heat to be shed by the cooling system so radiators, water pumps, and fans must be matched to the engine. The addition of a turbocharger will both boost power as well as compensate for altitude and also help reduce "smoke". Think of it as the OEM way of beginning with a basic model and adding "options" to create a different product.

I am not sure about the 5000 series line.But I know for a fact that the 7000 series and above especialy the 8000 series.It is all in the computer that determines the HP rating.Yet you can not pull the computer on example a 8420 and put it in a 8120.Because the complete tractor will shut down.The pumps on these are controlled from the computer.The days of turning an injector pump up to get more hp are over on todays modern Ag tractor and although the smaller utility line of tractors are not as complex I am sure this still remains true.

I would think more than a computer chip is involved in increasing the HP. Bigger valves, camshaft, injectors, turbochargers and the like should be the answer. Right?

I just wish the John Deere website gave more info. Their web site shows even the base 5103 with a turbo-charger. Can that be right? See the link below.

I am thinking of getting the four wheel drive version... but it's $4000 more....! I have a lowland swampy area that I will have to cross a few times a year. My friend says save the four grand and just cross in the dry season. Would four wheel drive help in other situations? The website says less "ground compaction" and other benefits. Any thoughts?

I may have to go visit the dealer, maybe if I leave my wallet at home I can escape without buying....

Thanks for the responses.

Here is a link that might be useful: 5103 engine turbocharged?

Visit the boys at tractorbynet and consult actual owners. They'll answer your questions on JD compacts and larger models:

http://www.tractorbynet.com/forums/jd-buying-pricing/

Bill

Front wheel Assit is good if your going to have a loader well worth $4000.00 for that alone.Try going into a pile of gravel or heavy dirt and you will instantly see the differance in the two.

As for compaction again true especially with ground engadging attachments.Less rear wheel slippage means less down force less foot print.If the rear wheels do not slip there not going down in the soil to create compaction nearly as much.However if your going to use the tractor for mowing either a mounted or Batwing type mower or hay conditioning and bailing hay.No need for FWA because if its that muddy you have no business out there anyway.

As for the Computer module being the main difference in HP rating ask your Local John Deere Tech see what he tells you.

If your going to get a cab and AC remember the AC takes HP if your getting an open station tractor you can get buy with less HP.

Land owners east of me and west one west has 5203 only mows 10 acres with it 509 mower does great job but when new fuel filter stopup about 10 hours on meter. One on east he got it feb. 07 5103 his filter stopup to about 20 hours on meter we changed it then fuel pump silnoid would not turn fuel on sometime at starting but retires and start. Took in for repairs fuel system had loader mounted I toldd that if engage ground needed water in rea tire he did not like water in rear tire because mess when flat but with new loader they put water in rear tires but still to lite in rear so we put my box bade on rear to help and it did have better traction. my best advice would be to get tractor and fuel filter at same time drain fuel tank a few times open the drain cock until just fuel coming out. have in sale to add water to rear tires. Now to spend the money for rear wheel weights if going to engage the ground box blade are scoop stop tractor and spin on top ground tamdeen harrow or turnning plow it want move. They are real nice tractor but lite in butt. In some farm magizines there good deal like 2 axle trailer mower box blade post hole digger in one package. I would take into fact 5103 burns less fuel other than that coin toss on power I can't tell which one has less power are more nice tractors.

These are great small tractors. The 5103 thru the 5303 are the same tractor, frame and engine. Just bigger tires and more fuel for the larger hp sizes and a turbo for the 5303. The 5404 is a newer size and I really don't know that much about that model. I bought a new 5303 in 2004 and have had good service with it in the last 3 and a half years. It now has just over 930 hrs on it. I use this tractor here on my beef farm for moving rolled hay, mowing with a 8ft. dise mower or our 9ft. haybine. It pulls a 10ft. bush hog just fine or an 9ft. wheel disk. I have even pulled 3 - 16s turning plow and also rolled some hay with our old New Holland 850 hay roller. The 5303 has plenty of power for its size. It is a little lite for the hp that it has. I had fluid added to my rears, 4 suitcase weights on the front and a set of rear wheel weights on the back. My 5303 now weights 7200 lbs. with me and box scraper on it. Only problems that I have had with it was a bad starter after about 6 months and they replaced that under warranty. Repair man said that they had been having a problem with the starters for this model at that time. The engines in this tractor is a proven Deere engine not outsourced to some other company.