4X20 series

bigblock · Jul 10, 2004

My computer has been giving me problems so I haven't been spending very much time here lately and may have missed some of what I am about to share. Please forgive me if I'm covering old ground.

I just happened to pick up a brochure a couple of days ago on the new twenty series tractors. It appears that the new series is not meant to replace the present ten series but is an upgrade powerwise. There are four models: 4120, 4320, 4520, and 4720. All appear to be the same size physically and all weigh the same, 3700 lb.. They all share the same 2.44 liter four cylinder turbocharged diesel but the gross horsepower ranges from 43 to 58. All are available with either 12x12 power reverser or ehydro transmission except the 4720, which is hydro only.

The specs on the 400x loader are almost the same as the 460. The 400x lifts less than 50 lbs more less than 1 inch higher. Breakout force for the 460 is about 350 lbs. more than the 400x.

I was thinking about upgrading from my 4310 when I move North next year but I'm not all that impressed with the Twenty series. They look like overgrown 100 series lawn tractors. I guess a 4710 would suit me if I end up needing something bigger. I must be getting old but I like tractors that look like tractors. Square corners are alright with me. I think the Ten series or the 90 series tractors look better. Hey, we're all entitled to our opinion and I'm sure that they will sell plenty of the new models.

What do you guys think?

Bob

cowboydoc · Jul 10, 2004

I'm not sure why they didn't upgrade the loader specs. The purpose of the curved design was supposed to be increased strength. But then they didn't increase the strength. /forums/images/graemlins/confused.gif The motor will now be a JD powertech engine. The 58hp will be a best in class.

As far as looks I like the looks of them but liked the old style too.

I think they made a couple of bonehead decisions though. Why would they delete the draft control? That makes no sense. They give the tractor more power but then cut out one of the biggest helps in ground engaging activities and one of the main reasons for needing the extra ponies.

The other bonehead move, at least from my perspective, was only offering the 4720 in hydro. If it was available in power reverser they would have sold one to me. As it is I'll just keep the 4600.

BillyP · Jul 10, 2004

Richard, since all the 4000 twenty series are identical, they could make you a 4720 power reverser in a flash. All they would have to do is change a few decals and tweak the engine/injector pump (whatever they do to get the extra HP out of the same engine).

Most likely you could buy a 4510 reverser and get the dealer to tweak it?

cowboydoc · Jul 10, 2004

Unfortunately the dealers are prohibited by federal law from doing anything like that. If they even know that you did they are supposed to turn you in. I did turn it up on my 4600 but I did that myself. On a brand new tractor still in warranty I would be hesitant to do that.

bigblock · Jul 10, 2004

I agree with you on the 4720. If I got one I would want the reverser. I don't understand why they offer it on the other three and not the 4720.

Bob

timb · Jul 10, 2004

I'm thinking that something in the tranny/clutch pack/rear end isn't up to the torque of the new 4720. Otherwise it would be a very strange option restriction since they are still making the reverser, the engines are all identical form factors (bolts right up), and it would take zero extra effort to make it available.

I did eventually get an email back from Deere corporate confirming they dropped the draft control because it simply hadn't sold much.

Glad to see you now have to fit under the bell curve and can't work outside the mainstream.

Bob - if you want a 4710 move fast. I almost missed out - my dealer had to go to Vermont to get me a 4710 reverser. There are (or were) more hydros available unsold. There is also a $900 or $1000 rebate until the end of July.

bigblock · Jul 10, 2004

I can't believe that the reverser is not up to the power of the 4720. Deere has power reverser transmissions in far more powerful tractors than that.

As for getting a 4710 now. If I get through the next few months without losing the 4310 I have now and my Corvette I'll consider myself lucky. Besides, I don't know that they aren't going to continue to produce the 4710.

Bob

Woodbeef · Jul 10, 2004

Hey Doc,

Is JD embarking on a new campaign to make the highest hp tractor in each series from now on shiftless by anychance? They've already done it with the large frame 7020s and now the 4020s. Will the 6030s and 8030s be the same I wonder?

cowboydoc · Jul 10, 2004

Tim,

The reverser will handle plenty of torque. I don't think that's the reason. My dealer is trying to get an answer.

Woodbeef,

I don't know what they are trying to do. I haven't seen any news on anything new in the 6000 and 8000 series.

timb · Jul 12, 2004

Bob -

I'm not saying that reversers per se are limited in power handling. Every transmission on the planet has it's input torque limit somewhere. The 4710 hit a peak engine torque output of 108 lb-ft. (owner's manual spec) where the 4720 has a max torque of 154 lb-ft. (a 42% boost!) Even if the tranny had a healthy reserve handling before - the 4720 may simply go over that limit. The 5000 series does not use the same reverser transmission - yet the 5220 peaks around 120 lb-ft - even the 5320 only puts out 144 lb ft peak. The 'new' Twenty series engines are potent, no doubt.

Since JD is still going to use that tranny in the rest of the Twenty series line - and since so far I can not find a single bolt or screw difference in the engines it looks like the reverser would fit a 4720 with zero extra effort and without any need to keep any unique extra components around on JD's part.

I can only think of three reasons to not offer the reverser on the 4720.

1) the tranny can't handle it (or perhaps with that tranny in place the range box, or rearend, or... can't handle the torque - remember no one publishes how much power a hydro bleeds off of the rear wheels so maybe with the hydro in place it bleeds off enough torque to be safe for the downstream components ) or

2) possibly it's a pollution spec thing with the big power motor, or

3) another (as Cowboydoc so aptly put it) 'bonehead move' with this new series. /forums/images/graemlins/wink.gif

rockyridgefarm · Jul 12, 2004

Why do you guys keep whinin' about the 4720?

It ISN'T the replacement for the 4710.

A 4520 still has awesome power and HAS a reverser.

You need to look at the 4720 as the baddest HST Tractor going.

If you NEED a bigger reverser than the 4520, Deere has plenty to choose from. And if you really do need a reverser that big, you probably NEED to look at them.

Remember, one of the big ideas that was indicated early on, was that Deere would be simplifying the model structure. I am amazed that there are so many models, still.

Dropping draft control was pretty lame.

cowboydoc · Jul 12, 2004

Why do you guys keep whinin' about the 4720?



I keep whining about it because to me it would have been an answer to some problems for me. While I love the compact and being able to go around tight spots, in and out of the barn with ease, putting in posts, etc. etc. that makes the compact ideal, it is underpowered for my uses. Ideally I should be using something like a 5320 or 5420. I'm not going to give up the compact though because of it's small size. The 4720 was the answer for my problems. But I don't care what people say I know that the hydro robs more than a couple hp. It's more like 20%. Take 20% off the 58 hp and I'm down to where I am now. With the pump turned up on mine I'm making 43 pto hp. The 4720 with the hydro would probably be close to this.

My problem is when raking hay, moving hay, pulling a mower, harrow, disc, aerator, overseeder, etc. I run out of power and have to go too slow. I like to be able to go as fast as the job will let me. That isn't always the case with the 4600. With the 4720 with a gear transmission there would be a great improvement and get me up to the power or a 5320.

That's why I'm whining. It's like giving candy to a kid and taking it away. Man let the crying begin. /forums/images/graemlins/grin.gif

KNotMe · Jul 12, 2004

But I don't care what people say I know that the hydro robs more than a couple hp. It's more like 20%. 

Where did the 20% come from?

Kyle_in_Tex · Jul 12, 2004

( But I don't care what people say I know that the hydro robs more than a couple hp. It's more like 20%. Take 20% off the 58 hp and I'm down to where I am now. With the pump turned up on mine I'm making 43 pto hp. The 4720 with the hydro would probably be close to this. Man let the crying begin. )

Let me be the 1st to whine! I think there's going to be some minor pump adjustments to the lesser HP 20 series machines. I like the torque #'s a turbo gives.

MANUFACTURER John Deere

MODEL 4720 Compact Tractor (58 hp)

Engine

Manufacturer John Deere 4024T

Aspiration Turbo

Cylinders/Displacement, cu. in. (liters) 4 / 148.9 (2.44)

Cylinder Liners Cast-in-Block

Performance

Advertised PTO HP (kW) @ Rated RPM 50 (37.3) @ 2400

Engine Gross HP(kW) @ Rated Speed 58.1 (43.3) @ 2400

Woodbeef · Jul 13, 2004

Hey Doc,

Just out of curiosity,do you happen to know if anybody has actually dynoed any of the 4x10s after they've had a few hours on them? Would be interesting to see the geared vs hydro figures from infield tests........Man this is going to be a weird comment coming from me,but I tend to think you are on the right track with your idea on how much the shiftless tranny robs hp. Be nice to know a bit more about the amount.

timb · Jul 13, 2004

WARNING! Dangerous hydro-vs-gear comments follow! /forums/images/graemlins/wink.gif

(Not saying one is intrinsically better than the other but there are engineering differences whose total impact is not usually published.)

Running a PTO dyno would be interesting but it won't reveal the whole story. As far as I know those tractor dyno's are not 'rolling road' types so the the tractor is effectively parked. In that case the PTO readings (hydro vs. gear) will only show the 'parasitic' loss of running the tranny pump with the tractor stationary - and that's probably only going to be the couple of hp usually stated.

Now - with the tractor under a 'draft load' moving both itself and the 'implement' and the pump then meeting more hydraulic resistance - that PTO loss % number may climb relative to the gear version as fluid power transfer is simply not as efficient as a gear train.

But - there is also likely to be a difference in how much power is making it to the rear wheels for that draft effort. Until someone does a Nebraska-like drawbar hp test - with properly ballasted tractors we will only be able to guess. /forums/images/graemlins/confused.gif

cowboydoc · Jul 13, 2004

Until someone does a Nebraska-like drawbar hp test - with properly ballasted tractors we will only be able to guess.

They have done them on utility tractors and it is typically a 20% loss under load. The big combines with the hydros are 30-40% power loss under load, pulling. But you don't pull with a combine so it's usually a non-factor. That's why you see hydros in combines and not tractors. That's also why you're seeing the IVT's and other infinite gear transmissions and not hydros. The power loss is too great.

Woodbeef,

As of right now, "on the record", they don't test the compacts like they do the bigger tractors. "Off the record" these tests have been done and the power losses under load are in the 20% range.

rockyridgefarm · Jul 13, 2004

OK, Doc, your logic is great. With one exception. Aren't you are wanting Deere to offer a stock machine that is an improvement over your tweaked 4600? The new stock machine is superior to the old stock one, and tweaked, wouldn't it be capable of similar improvements as your 4600?

cowboydoc · Jul 13, 2004

Yea but you can't tweak them and still get warranty coverage.

SteveH_CT · Jul 13, 2004

Since I believe you know, or even better, are related to someone who does these tests... why aren't they done "on the record" for the compacts? Are they just too busy testing the larger equipment? I'm just curious, since I'm someone who enjoys having hard facts that are gathered by standardized testing - not opinion and hyperbole stating "mines better than yours" because the sales brochure says so. I tend to look at stats in brochures to be of questionable veracity... with the exception of JD's of course /forums/images/graemlins/wink.gif.