Recentley just started running this D7E LGP and I have really started to like it! Getting used to not having a deacclerator was pretty tricky, but the way they have the gears set up where you can increase and decrease speed from 0.1-3.5 you really dont need a deacclerator, it ust very hard to get used to. My opinion: I think this particular setup (LGP) is awesome! You have the power of an 8 but can go just about anywhere that a 6T LGP vpat will go. I was pretty surprised when i looked at the ground pressure between those 2 machines. The 6T has a ground pressure of 6.4 and so does the 7E. It is a PITA to finish medians and shoulders since the blade is so big, but it can be done. I really think the 7E lgp is a great machine, i would like to see cat attempt to put a vpat blade on it. Now as for a D7E standard track i really dont see a place for them when you can get a 8 but thats just me. Whats some of your guys opinions??? Fuel consumption: In a hard push most of the day i burn between 85-95 gallons, finishing and doing light for burn between 45-55
Just talking about the 7E today wondering if Cat is going to produce other sizes.
I wouldnt think they would. The price tag on a 7E is almost as much as an 8T, so i wouldnt see anyone buying a 8K over an 8t when they both can do the same amount of work.
An electric 8 would likely do more work, based on the performance of 7E. The issue I see and have heard from owners of 7Es, is that it still bills as a D7 on any hourly bid work. They say they can't bid 8 rates for it, and there's no 7E category in with the 7s. So, basically, they get to pay more to buy it, do the hourly work faster, and get paid the same as a smaller machine. I would say that's the biggest issue facing them so far.
I really like the looks of the new D7E. The lgp model sounds like the perfect machine for alot of tasks with its impressive performance. Not to bad on fuel either. Be interesting to see how they hold up over the years. www.cat.com/en_US/products/new/equipment/dozers/medium-dozers/18429156.html
Yea got to push side by side an 8T and the 7K will hang right in there with it! Today ran some pretty steep slopes (2:1 and a little steeper) with it and have to say that its relly well balanced! Im sure the 40 inch pads help alot
D11 with electric drive system, now that I would like to see. Would push dirt brilliantly. Plus it gives electricians like me more job options.
How long have these been out? Can someone explain to me where the rotation becomes electric and where the electric becomes rotation again? i.e. how many gearboxes are the same and how much is not? What voltage and current roughly are the main cables? AC, DC, inverter drive? Where do the hydraulics and other systems get their energy from? Is there a place to plug in a coffee pot?
Basically, it's like a diesel electric drive dump truck or locomotive. The diesel engine drives a high voltage alternator that produces, say, 2000 volts AC. This voltage is fed into the drive system box, where it is rectified into DC high voltage, this DC voltage then goes into the IGBT inverters that convert the DC back into AC power that supplies two large electric induction motors. These two motors then drive the left and right hand final drives. When braking, the electric motors no longer consume power, they generate voltage which is fed back to the IGBT inverters and is onfed to a resistor grid where the power is dissipated as heat. On an electric drive dump truck, the hydraulic pumps are driven by the engine, I'd assume the D7E would be similar.
Just be patient
Yair . . . An old bloke once told me to listen carefully to a man who speaks his truth with an economy of words. (he gives a speculative grin) Cheers
I have heard rumours of a Cat mining dozer with electric drive, but I'll believe it when I see it. Would Cat bother since they own the mining dozer market anyhow?
Car and Driver had an interesting article on the D7E www.caranddriver.com/reviews/caterpillar-d7e-feature-test
Sure looks like the old Terex, but they always were ahead of their time. Just needed a quieter engine
They should have left their radiator up front and moved the engine to the rear instead.
Jerry, if you're out there, do you have any further experience with the 7E? I know you ran a demo awhile back.
How is it that they do not have elevated sprockets on the d7e?
DPete I missed this, as I have not spent much time here in a while. Finally getting busy again. Sorry to say I have not had any time on the 7E since the demo I wrote about so long ago. I still say that it was the nicest dozer I have been in from an operators view, but as an owner, I am concerned about the durability of the electronics. My experience with my D-8T has me leery of all the electric over everything controls. In 9,000 hrs, I have spent as much on electrical repairs as I have on undercarriage. It seems that the wiring is too light of a gauge wire to hold up to the constant vibration encountered in a dozer. Add that to the need to replace a faulty ECU for any number of problems, and that when the ECU internal battery looses its charge, it seems to quit working and need replaced. I mean the whole thing, the battery is non replaceable.
Yair . . . JDOFMEMI . I saw you post about electronic repairs versus walking-gear repairs and, looking through my dinosaurs eyes, it left me speechless . . . then I see a current discussion on here about 8H's and K's being bought for big bucks to go to Africa because they can keep them going with limited mechanical knowledge. It makes me wonder (again/still) just how far we have come in machinery design. It seems to me the dirt and rock and remains constant but we devise ever more complex and fragile ways of shifting it. We can't do anything these days that we couldn't do fifty years ago and back then, in real terms we did it at less cost and, in most cases, turned a better profit. That's as I see it anyway. Cheers.
I have a Toyota forklift 7 series. It is electric with ac drive to an induction motor on each drive wheel and a tricycle rear tire. The independent motors can counter rotate. Neat..... but when a bunch of wire wrappers build stuff they get to call the shots and the iron gets hind teat. Old iron people can fix is a hot commodity.
Well said Scrub, all the modern goodies come at a price. Ease of operation is supposed to result in more cycles or lower cycle times which can't happen if you're waiting on a tech with an ET to pinpoint a problem that you never had with older machines.
I agree Scrub, very insightful..........
D-7E I'll be darn. He//, I'm thinking 48a ***, I recon I live in the past. O.K. then