You bring up two very interesting points:
(1) Deere 5083E - 4.5L Turbo 4 Cyl putting out 83hp at 2400 RPM
Kubota M8540 - 3.76L Turbo 4 Cyl putting out 84.6hp at 2600 RPM
(Just a side note the Deere is a wet-sleeved engine while the Kubota is a parent bore engine)
So we have a smaller displacement engine putting out more HP at a higher RPM, which is understandable to a point. My question would be which engine will last longer?
(2) Deere 5083E - 69 PTO HP at 2400 RPM
Kubota M8540 - 75 PTO HP at 2600 RPM
How does a larger displacement engine running at a lower RPM lose more HP at the PTO than a smaller displacement engine running at a higher RPM? Are there any Kubota experts that would like to explain it? (I cant wait)
My question to a Kubota M8540 owner is what is your PTO rated speed on the tachometer? I dont know and I cannot find the information on Kubota's website. The reason I ask is because if PTO rated speed on your tach is at 2400 RPM, how many PTO HP do you actually have when the PTO shaft is turning at the correct 540 RPM for your implements? And if you run at 2600 RPM to get the advertised 75 PTO HP at what RPM is your PTO shaft now turning? In this case we would have a smaller displacement engine turning higher RPM's (increased wear, shorter lifespan) and an implement running at a higher speed then the manufacturer intended (again - increased wear, shorter lifespan)
Dont get me going on how a tractor that is almost 2,000 pounds lighter can lift over 1400 pounds more at the 3-Point Hitch (a 5400 pound tractor can lift 4630 pounds? What is even more impressive is that the optional 3-Pt lift capacity on this tractor is 7055 pounds! If the Deere weighed 300 pounds or so less, the Kubota could pick it up on it's 3-Point! Amazing!!!) or about how some tractor companies rate thier hydraulic flow...
Next week we can look at Kubota's "Competitive Comparison" of the MX5100 and the Deere 5055E, believe me it is an interesting comparison.
On question 1, Kubota uses variations of the M8540 engine (V3800DI-T) in several tractors, the M8540, M9540, M96S, M108S,
M100X,
M110X. I'm not aware of any problems with this Kubota engine. It does use 4 valves per cylinder and center direct injection, perhaps that explains the power.
On question 2, you will have to ask JD why their machine is less efficient, I have heard that perhaps there are more losses between engine and PTO than for the Kubota.
On the M8540, the engine speed is 2205 rpm for a pto speed of 540 rpm. I had the same questions as you, what is the PTO power at 2205 engine RPM, Kubota does not publish the figures, I contacted Kubota and was told that it does make 75 HP at the PTO when the PTO is at 540 rpm.
See this post for more info:
http://www.tractorbynet.com/forums/...lly-kubota-rated-speed-395-a.html#post2475636
So the answer to your question is that the M8540 will make 75 PTO HP with the engine running at 2205 RPM and the PTO turning at 540 rpm.
Three point lift is built strong on the Kubota: the M8540 can lift 4600 lbs standard and something like 7000 lbs with the option. My M8540 never weighed just 5400 lbs; with filled rears, FEL, bucket, canopy, and grill guard it weighs about 9600 lbs. With a cab, cast rear wheel centers, front weight bumper and weights it would be around 12,000 lbs.
