I started this tread to get some input on why the D7 H’s and R’s are not as popular as high track 6’s and 8’s if you look at cat used website there are around 45 high track 7’s over 300 6’s and 180 8’s I had never ran a newer 7 until a month ago when the Boss bought a 7R2. 10000lbs and 40 hp there is a noticeable difference from a 6T. Weighing around 62000 without the ripper we can still haul it with a 3 axle trailer and not have to have a cheater axle on the truck. I know new prices are around $80000 more than a 6T and $100000 less than a 8T of course they had to quit making the 7R now and the 7E looks to be a $500000? Machine. I will try to post some pics of the His new 7 until then I am curious to see your comments on this topic
D7's are too big for many projects, too small for others. No good at all for rock work, too heavy for soft ground. Still a nice machine, just not that useful in most situations.
I have to agree with you about the soft ground I always wondered why they didnt have a XW option with 28 or 30 inch shoes. Were we work 24's are sometimes not wide enugh but a full blown lgp would be over kill not to mention the extra uc wear and thoes dredful straight blades. As for being to large for small jobs and to small for large jobs the same could be said for any number of dozers a D4 might be to big for leveling a garage floor and a D11 may not take the place of a komatsu 575. Here in Iowa we dont have any rock so I wouldnt know, are they not heavy enugh?
I really liked the D7H I ran a couple years back they push good. I have found Alberta has more then a few 7s but then again we like brining iron thats to big for the job compared to some places
Lately all I've seen sevens used for is landfill work. They have always been too big for pioneering logging roads and too small for production land clearing. I've also heard many an operator state that they were unbalanced in how they push dirt. Unless you have a big multi-shank ripper on the back they tended to dive when they picked up a blade full. I do remember some loggers that liked to take the D7 motors and install them in the D6 tractors. I've run into a couple and they would turn the tracks through the brakes in first gear.
Here in my part of Aussie we use 7s in logging, agg work,some genral contracting, but 6s are still most popular don't see many 8s, 9s and 10s less it's on a major highway, or big civil job and your right 7s still legal on a triaxal float. so don't need that dolly. cheers Leroy
Seriously? Back at home you won't find many machines smaller than an 8 doing logging road pioneering work.
This time I was thinking the exact same thing :beatsme
Around here it seems to be all D6's and 8's, D7's are more rare and D9's are really rare. Only D7 I ever ran was for a demo contractor.
Where's back home?
Southern British Columbia, the Kootenays to be exact.
:notworthyFind D7G to be a terriffic machine here. Pull No. 70 Cat pan with it, blade off, blade on push D8K pulling Cat No. 80 pan. Also use it for lots of dozer work also. Easy to move on a tandum or tri-axle lowboy. Has made me a pile of money over the years.:drinkup
I too have a D7G, I find it to be the right size machine for most all the jobs I do, a D6 would be too small and an 8 is just to big to move around. My 7G is a 1976 and it has just worn out the original tracks, it has about 900 hours on the new ones, it has a skin cab over the rops and I installed a 46,000btu chiller unit in it with the condensor unit on the top of the cab. I for one think the 7 is a very versatile machine. I have two older 7s, two HD15a Allis Chalmers and a D9 but the D7G is the machine of choice for most of my work.
Alco, I believe you can run a wider road in Canada than down here in Washington State. Those big off highway haulers you fellas like to run generally take a little wider path. There isn't a lot of private roads that go directly to the drop or the mill so we still have to run legal highway loads. What say you?
John, it's all highway legal loads on highway trucks where I'm from. We don't have any off highway stuff at all, nor do we have private roads to the mills. The area I'm from is directly north of Spokane, about half an hour north of the border. I spent ten years building logging roads there, so I can tell you they build with a thirteen foot road surface as a rule, and use pull outs to get trucks past each other.
I have operated many D7´s of different generations, those that had a ripper on the back had very good balance in dirt dozing work, especially the high horse D7E. (not the new electric...) I found the D7F with the lighter motor to be somewhat inferior in that respect. In fact I have found any dozer without a ripper at the back to be short of balance and traction.
Sounds like we have about the same specs for roads then except that the D8 blade is usually 14 foot wide. We also have a spoil issue and that nothing can go over the bank. That's why excavators seem to have taken over the pioneering work. Usually the D6 just pushes dump truck loads out. You don't need the weight, width and power of a D8 for pushing pit run. I was thinking maybe it might be steep ground but I believe you have plenty of that where you are too.
D7 Down the bottom of the world D7s were always popular for logging and roading. 17A s D7E F G and HD16s TD20s D85s. D7H and R seem to be the tool of choice at present. Some people do use D8s but alot of it depends on transport issues and soil conditions. Also in steep country 30 ton plus diggers and a D6 size dozer is a popular choice; most of the work I do. John C had a mate from NZ visit oregon and canada, and he was told that sidecasting dirt over there was now a big nono and has to all be carted away ? This must make forestry roading up there horendously expensive, there must be some areas it would be plain unprofitable to log and would have to be left. Would certainly be the case here if it ended up with rules like that here. As alot of the land were I am is first crop and is getting roaded as they get to it. Cheers Merv:drinkup
D7 Just to add abit more. Twenty plus years ago D7 size machines were the main choice for logging, but now as tractors like the D6H/R and D65-12 have all grown to the old D7F size of 180 hp and 20+ ton they are more the choice for logging and you never see a D7H skidding logs. Merv
D7h We use D7H 's all the time in forestry roading here in New Zealand. And you cant get the new D7E here yet, only the D7R II.
I wonder how the weight of the new D7E (electric) will affect it's popularity....the 6R Series III runs from 40-51,000 lb depending on configuration. The D7E is 57-62,000. Is that in the range of too big for small work and too small for big work? Maybe they should have built a D6 electric instead.
New D7E Electric I had to convert your US pounds into metric Tonnes, but I see it comes to 28 tonnes, witch is the same as the D7H with rippers. ( Hey why do you guys use pounds for something as big as a dozer or digger? I know you have US Tons.)
Tim, Sometimes I wonder why we do things....like the construction plans we get. They're in all kinds of mixed units...decimal feet, metric, feet-inches and fractions of inch, surveyor's units of miles, chains (66ft.), links (.6ft.) & rods(16.5 ft), and angles in degrees-minutes-seconds or decimal degrees. What a mess.... BTW, In the US lumber in in 2x4, 2x6 etc....how is lumber measured in metric countrys?
Metric v Imperial We changed over in 1967 I think it was, ( from Imperial to Metric ) so any plans or anything official is all in metric. But if you or I were just talking about a piece of wood we mine say "go pick up that 4x2 or 6x2" but if a builder was buying timber he talk about a piece of 100x50 or 200x50.
When I say in New Zealand I shod also in Otago ( in the south of the South Island of NZ.)
New D7E Electric Hey does anyone on here have a new D7E, is cat having any problems with them? And how much for one ($$$) ?
I saw a used D7E on catused.com $626,000 usd had 196 hrs on it I havent priced any new dozers but you could probably get a new 8T for the price of the new D7E.
D7 Whatever the price of a new D7E is in the states, it will be double that by the time it gets to the bottom of the world. And our hourly hire rates are probably less than you get in the US. What are you getting for your D7H Timdozers. Guy up here was running his D7H fo $170 hr and D8R for $200hr. This is pacific pesos, about $120 and $140 US. And what are you guys in the US getting for a D7H. ? D7Hs have been exellent tractors tho, have heard of several doing 30 000hrs, with full rebuilds around 14000hrs. Merv
I'm on a D5G it is charged out at $120 an hr deisel is supplyed by the mine it gets paid for 10 hours we may get 8 clock hrs just the nature of work I've done alot of roading on D6"s 7"s 65"s 8"s etc when cat D6"s only had S blades I found the D7"s better with SU blades now the 6"s have simalar blades there"s not nuch in it esp with diggers helping. If the trees are bigger and the rock hsrder the hill is steeper the bigger the better. I was in NZ roading with a D8R charged out at $200 per hr. Over here the seem to higher and the work is easier.
D7hii The boss keeps his prices to himself but I know he gave a guy a bill for $160 an hour for a D7H. We 7 Dozers D4E ,D6H one D7HI and a D7HII ,D9N , XCMG TY230, Shantui SD32 ( the last two are from china, the same as a 1970s D65 Komatsu and D85.) The D7HII we brought new in 1993 and now has 35000hrs on it, ( One operator )
D7hii Our D7HII with 35000hrs on it, was rebuild at 20000hrs by Gough's ( that's the NZ Cat dealer ). Gough's said most of the bearings in the transmission did not even need to be replaced, (that's one operator for you!)
D7's in SE Oz Yep, your right Leroy, D6's are more popular. However, a D7 for forestry work is spot on, especially new road construction, they have a lot more ripping power + grunt to get big hardwood trees down. Let downs are with big rippers and forestry canopy I reckon you are right on the weight limits for a tri-axle float. And can be a little big for farm jobs (access problems). Also (and I am open to be told I'm wrong) a new D6 is around the $650K mark and a D7 is bout $800K, fair jump in price. Anyway, guess it is what your doin with it. Cheers O
Hi Merv, I can't talk about the state of Washington, but in Oregon the degree of slope in the ground dictates whether or not you can sidecast material. If it won't stick to the hillside, it's too steep and that section of road must be built as "full-bench", or 100% endhaul. I haven't worked in the woods for a while now, but I believe that the cutoff slope is 66%. As far as the talk you guys have been having over the size of cats used for pioneering roads, it's a moot point anymore as excavators do most all of it anymore. As John C said, the D6 size is great for knocking down and working in loads of rock/ballast/metal. The D7 size is handier than the eight to transport, but if there's any quantity of dirt to be moved or rock to be ripped, an 8 is the machine for the job. A typical spur road gets a 14' subgrade and 12' of surfaced width, and mainlines may get 16' or more of subgrade and surfacing to match. -72V aka "Powdermonkey"
I worked at a minerala sands mine in western Aus for over 5 years an we had at least ten D7's. The reason the company used them was to push the tailings dams back in...under neath is a thick shake type slime so anything bigger would sink an anything smaller was useless. They did an unreal job an over the years never seen one that had to be dragged out.
Thanks for that 72V. I can see those sorts of rules, becoming more common in my part of the world; Had one job last year on a forestry job where there was to be no sidecast because of the visual impact; was on a high steep ridgeline with about a 60 degree dropoff the side. It was all done with a 35 ton digger and 2 ADTs. Hardly needed a dozer on that job. But would have been expensive, just as well it was a big block.
D6 v D7 We have got a D6H and two D7H's. We have found the D6 is just a bit to light for the big stumps etc(got 20000hrs on it now), the D7 has just got that bit more power and the rippers are built heaver for the work we do, but in saying that we are looking more and more at the D8. The D6 is out on dire hire now days.