overworked
Senior Member
I would keep your d6 and buy the d8t with the price of the 7e it's not worth it, just a over priced d6. D7e pushes liked6r and cost like a d8
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D7e or d8t ?
- Thread starter BLACKEARTH
- Start date
I have a D-8T, and it is only the second NEW machine for me. It has right around 9,000 hours on it, and until recently has been a very good machine. It was bought during the building boom, and spent the first 5,000 hours doing GPS finish work. It had nearly zero problems in the beginning, and doing finish grade work, the original undercarriage went 5,500 hrs. It then got rails and sprocket segments, as well as much tougher duty work, and made 8,800 hrs before getting all new Cat undercarriage, with the exception of the idlers, which were welded up and resealed by the Cat dealer. The undergear ran about 40K, so added to the rails and segments earlier, I got 8,800 hrs for under 60K.
There has been very little mechanical problems with the machine. What there has been a lot of is electrical problems, starting about 6,000 hrs, and getting progressively worse. The ECM is the latest in a string of electrical problems. It was causing the machine to overheat, even though there was no mechanical reason for it. It turns out the fan is variable speed, and controlled by the ECM. The ECM would not tell the fan to speed up and cool the tractor down, but it was not running slowly enough to tell with out a RPM meter to check it with. I would think in a failure mode, it would default to the highest fan setting, but that does not seem to be the case. It has also had sensor issues, wire looms with short circuits in places that visually check out good, just broken wire inside the coating due to too light of a gauge wire, and a host of other hard to troubleshoot and repair problems.
I have been very happy with the D-8T, until the electrical gremlins set in. At the current time, the money spent on electrical problems is neck and neck with the cost of the undercarriage. I would have never expected that.
I ran a D-7E in a demo session once, and thought it was the best dozer I had ever ran, but looking back on it, due to all the electronics I would be afraid of it. I am NOT talking about the drive system, but all of the machine controls.
If I had to buy another comparable dozer, and there were no limits due to emissions regs, etc, I would look for a low hour D-8R series II. I believe when looking back, it will be the last truly great D-8. As a small to mid sized contractor, when making a purchase such as a new D-8, it needs to work reliably for many years and be able to be counted on to be available.
The "hidden" problem with the electrical issues is the time to repair it. I have been down for 3 weeks getting the latest problem diagnosed and repaired. If it was a mechanical problem it would have been a day or two, but electrical eats up time and money like nothing else. With the ease of operating comes a difficulty of repairing. These machines are too costly to be built as a throwaway like so many other things in our modern life.
There has been very little mechanical problems with the machine. What there has been a lot of is electrical problems, starting about 6,000 hrs, and getting progressively worse. The ECM is the latest in a string of electrical problems. It was causing the machine to overheat, even though there was no mechanical reason for it. It turns out the fan is variable speed, and controlled by the ECM. The ECM would not tell the fan to speed up and cool the tractor down, but it was not running slowly enough to tell with out a RPM meter to check it with. I would think in a failure mode, it would default to the highest fan setting, but that does not seem to be the case. It has also had sensor issues, wire looms with short circuits in places that visually check out good, just broken wire inside the coating due to too light of a gauge wire, and a host of other hard to troubleshoot and repair problems.
I have been very happy with the D-8T, until the electrical gremlins set in. At the current time, the money spent on electrical problems is neck and neck with the cost of the undercarriage. I would have never expected that.
I ran a D-7E in a demo session once, and thought it was the best dozer I had ever ran, but looking back on it, due to all the electronics I would be afraid of it. I am NOT talking about the drive system, but all of the machine controls.
If I had to buy another comparable dozer, and there were no limits due to emissions regs, etc, I would look for a low hour D-8R series II. I believe when looking back, it will be the last truly great D-8. As a small to mid sized contractor, when making a purchase such as a new D-8, it needs to work reliably for many years and be able to be counted on to be available.
The "hidden" problem with the electrical issues is the time to repair it. I have been down for 3 weeks getting the latest problem diagnosed and repaired. If it was a mechanical problem it would have been a day or two, but electrical eats up time and money like nothing else. With the ease of operating comes a difficulty of repairing. These machines are too costly to be built as a throwaway like so many other things in our modern life.
Scrub Puller
Senior Member
Yair . . .
Bloody amazing (and frightening) is all I can say.
Cheers.
Bloody amazing (and frightening) is all I can say.
Cheers.
Electronics will only get more involved as we go. Its cheaper to put a wire from point a to b with controls then an actual linkage as of old. Understanding the electrical systems woill be key today on. Understanding PWM systems is a plus , the other , different systems use different voltages which sets another problem the echo effect. One system wigs out due to another irregular voltage , these can be lower than .01 . This floors your old school mechanic , because its doing one thing but the computer points else where. Old schools wants to go by his gut feeling. 953C went to neutral with brake locked while moving . Not a trans problem , temp sender was faulty telling the ecm to park it. And it parks without warning. New temp sender , ready to roll . 150$ part , trip to Lex and back up and running. The dealer would bill out around 1500 or more for this repair. If it were my choice , fuel would be the deciding factor. The 8T is solid , the 7E , well look at locomotive technology , underground mining technology , even cars . Electric drive its self is not specifically new , to a track tractor yep. But what do I know , I run a D39E-1 Komatsu .
old man dirt
New Member
Hi all Electrics dont be afraid of them.
Done a lot of reading onthis forum,mighty fine place to be.Well if u are a small contractor go the D7E dont let electrics scare u off.Look at Wabco some of the best machines ever made the only reason they are not around today the lack of understanding of electrics .Saw a company buy a fleet of Komatsu 630 trucks had nothing but trouble for 6 mnths when they shipped off a bunch of fitters to japan and got them trained up properly never had any more problems with them.Watched a lot of cat techs try to repair electrics with computers the only time i ever saw any good results was when cat was told put it on the float and take it back,then all sorts things happen.Could tell u alot of stories about electrics as far as i am concerned they are as good as u look after them.If u are having electrical problems that equate to the value of the track gear get rid of your electrical team fast that is your true liability.
Done a lot of reading onthis forum,mighty fine place to be.Well if u are a small contractor go the D7E dont let electrics scare u off.Look at Wabco some of the best machines ever made the only reason they are not around today the lack of understanding of electrics .Saw a company buy a fleet of Komatsu 630 trucks had nothing but trouble for 6 mnths when they shipped off a bunch of fitters to japan and got them trained up properly never had any more problems with them.Watched a lot of cat techs try to repair electrics with computers the only time i ever saw any good results was when cat was told put it on the float and take it back,then all sorts things happen.Could tell u alot of stories about electrics as far as i am concerned they are as good as u look after them.If u are having electrical problems that equate to the value of the track gear get rid of your electrical team fast that is your true liability.
Scrub Puller
Senior Member
Yair . . . old man dirt
I think if you read the post again you will realise comment is from a small contractor who probably does not have an "electrical team" . . . like a bloke I knew a few years back trying to put two blades wide of fenceline clearing around sixty thousand acres of goat country with a fairly new D6, it bloody nearly broke him.
I have no knowledge of modern machinery but have kept in touch with the industry sufficient to be aware that despite your assertions most heavy equipment of the present era has some inherent unreliability due to inadequately designed and manufactured electrical/electronic components.
No doubt this state of affairs will improve but to assert that all is rosy at the moment in the field of engine/machine management and control implies a head stuck deeply in the sand.
Cheers.
I think if you read the post again you will realise comment is from a small contractor who probably does not have an "electrical team" . . . like a bloke I knew a few years back trying to put two blades wide of fenceline clearing around sixty thousand acres of goat country with a fairly new D6, it bloody nearly broke him.
I have no knowledge of modern machinery but have kept in touch with the industry sufficient to be aware that despite your assertions most heavy equipment of the present era has some inherent unreliability due to inadequately designed and manufactured electrical/electronic components.
No doubt this state of affairs will improve but to assert that all is rosy at the moment in the field of engine/machine management and control implies a head stuck deeply in the sand.
Cheers.
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Hey mate if the transportation isn't a prob go 4 the d8 there have been a lot of good points raised by out her people here is my 2 cents worth.
If u look at what a d8 can shift in a day then compare it 2 a d7 then look at the fuel consumption the 8 is the clear winner and there still a very snappy and moonoverable the profit margine will b greater this will allow u to get more work and bigger jobs.
Also there is nothing u can do with a 9 that I can't do with an 8 and still use less fuel,except maybe in hard rock.
The pendulating undercarriage is brilliant better traction better use of the torque and a better ride and not really that much more expensive.
U will find u can trim with an 8 quite well once u get used to it I can about 60 mill by eye and arse over about 200 meters and with laser gear about 25 mill same distance.
The diff steer is a no brainier it's very reliable and it is impossible 2 slingshot the drives giving better component life 2 the drive line and the whole tractor really.
That way it's not so scary to hire someone to drive it ITS HARDER TO HURT.
I could go all day about the prose in my mind the only draw back is its harder to shift.
Something to remember but if your doing any chaining u gota have a mate 4 it or if its mate is smaller at least a direct drive machine to match it.
However if we're my money and someone mentioned this b4 about second hand I would b on the hunt 4 a series 2 D8R although a bit shorter they put more power to the ground use less fuel they still have a mechanical fan (less hyd) a better cooling system with a high speed fan put in my mind they are the ultimate ag dozer.
If u look at what a d8 can shift in a day then compare it 2 a d7 then look at the fuel consumption the 8 is the clear winner and there still a very snappy and moonoverable the profit margine will b greater this will allow u to get more work and bigger jobs.
Also there is nothing u can do with a 9 that I can't do with an 8 and still use less fuel,except maybe in hard rock.
The pendulating undercarriage is brilliant better traction better use of the torque and a better ride and not really that much more expensive.
U will find u can trim with an 8 quite well once u get used to it I can about 60 mill by eye and arse over about 200 meters and with laser gear about 25 mill same distance.
The diff steer is a no brainier it's very reliable and it is impossible 2 slingshot the drives giving better component life 2 the drive line and the whole tractor really.
That way it's not so scary to hire someone to drive it ITS HARDER TO HURT.
I could go all day about the prose in my mind the only draw back is its harder to shift.
Something to remember but if your doing any chaining u gota have a mate 4 it or if its mate is smaller at least a direct drive machine to match it.
However if we're my money and someone mentioned this b4 about second hand I would b on the hunt 4 a series 2 D8R although a bit shorter they put more power to the ground use less fuel they still have a mechanical fan (less hyd) a better cooling system with a high speed fan put in my mind they are the ultimate ag dozer.
DMiller
Senior Member
Planned obsolescence is key to keeping machines rolling off the lines, you stack enough high hour failure prone equipment or need to update with newer/faster PLC modules and more efficient electrical gear and the need to replace machines becomes ever greater.
My old AC machine is simple, straight forward hard parts, pieces that today are becoming scarce, that is the Achilles heel to those machines as is the electronics of the newer machines.
My old AC machine is simple, straight forward hard parts, pieces that today are becoming scarce, that is the Achilles heel to those machines as is the electronics of the newer machines.
Yes, but they may not like the trade in my case. It has really soured me on new iron, and buying good used models before the electronic infestation and getting quality rebuild work done seems to me to be a far better deal than new.
Construct'O
Senior Member
Your in catch 22,since you live and work in Calif ! There regulating you out of busniess or into retirement.It's coming even where soon or later. Either you will have to buy new or retro fit the old if possible.
Rebuild is on my list here.
As far as the original post goes and being close to the poster i would stick with with getting 2 more D6T or R's.Doing farm work here D6R or T is the machine of choice not D8T.You can own two machine for the price of one D8T.
You can be working two jobs at once compared to one with the 8.PLus when you have wet spring here like we usual have the 8 will be setting more then running.Can't charge farmers what the machine is worth,and moving will be a pain.
Guy close to be has two old 8H and has went to D6R in the last couple years because he can't charge what he needs too and get work to keep them running.They both have set all fall and he has been runing the R'S,each to his own.
This coming from a contractor that has been doing farmwork for the last 40years and still doing it.D6R high track has replaced nearly all the D7G around here.Reliablity,dependable and low cost to operate tops my list!!!!!!
I totally agree that the d6 is by far one of the best machines ever built.
But if u already own 6es why not go the 8 the dirt u can shift the hard rock ability if pulling scrub no matter virgin or light regrowth the spread ( distance apart ) is greater and daily country covered verses the fuel burn the 8 is actually cheaper to run front the contractors point of view and from the clients point of view it's also cheaper it may take a while 2 catch on,
But if look at wat it can do in an hour verse the smaller 6 it's still cheaper to run I 1st learned this when running 8s and 6s in the same paddock pulling and had just started converting the cost 2 an acre rate the cost to the cow cocky its by far more economical to have 8s.
I would strongly suggest comparing the component life of the two u will find the bigger tractor lasts longer because its not working as hard.
If pushing contour banks or dam sinking or turkey nest building the 8 is still the winner convert the cost to a cubic meter rate and u will find the 8 is in front it is also heavier and will give better compaction both from track rolling and dirt sliding on dirt.
The 6 may b easier to use on the batters but once u figer out the 8 u will love it.
It may b different in Luther parts of the world but in Australia our properties r big our paddocks r big our contours banks r long our dams r big so for the work done against the price of fuel verse the hourly rate and the component life as well as component cost u won't beat the 8.
And there not that hard to shift u only need a pilot to shift them here oh and 4 rows of 4 on the float.
Go to a nine and u need police escorts pilot cars permits a quad dolly under the float and its just a headache.
Obvisually a 6 or 7 is easier 2 shift 3 rows of 4 is plenty no dolly no dolly no pilot vehicle is a pice of cake.
But pilot cars are cheap and plentiful here so to shift an 8 is not that big a deal.
But if u already own 6es why not go the 8 the dirt u can shift the hard rock ability if pulling scrub no matter virgin or light regrowth the spread ( distance apart ) is greater and daily country covered verses the fuel burn the 8 is actually cheaper to run front the contractors point of view and from the clients point of view it's also cheaper it may take a while 2 catch on,
But if look at wat it can do in an hour verse the smaller 6 it's still cheaper to run I 1st learned this when running 8s and 6s in the same paddock pulling and had just started converting the cost 2 an acre rate the cost to the cow cocky its by far more economical to have 8s.
I would strongly suggest comparing the component life of the two u will find the bigger tractor lasts longer because its not working as hard.
If pushing contour banks or dam sinking or turkey nest building the 8 is still the winner convert the cost to a cubic meter rate and u will find the 8 is in front it is also heavier and will give better compaction both from track rolling and dirt sliding on dirt.
The 6 may b easier to use on the batters but once u figer out the 8 u will love it.
It may b different in Luther parts of the world but in Australia our properties r big our paddocks r big our contours banks r long our dams r big so for the work done against the price of fuel verse the hourly rate and the component life as well as component cost u won't beat the 8.
And there not that hard to shift u only need a pilot to shift them here oh and 4 rows of 4 on the float.
Go to a nine and u need police escorts pilot cars permits a quad dolly under the float and its just a headache.
Obvisually a 6 or 7 is easier 2 shift 3 rows of 4 is plenty no dolly no dolly no pilot vehicle is a pice of cake.
But pilot cars are cheap and plentiful here so to shift an 8 is not that big a deal.
Scrub Puller
Senior Member
Yair . . . Cam85. Bloody hell mate, its good to have someone on here who talks Queensland English!
I see a fair few dots there, but you're still a bit lousy with those commas and white space. (he grins)
Good post and I agree with you completely although I have never driven the modern stuff. I believe your comparisons in size of 8 versus 6 are valid going back to year dot.
Did you see the pictures of our 1965 scrub nines here . . . . . . https://www.heavyequipmentforums.com/showthread.php?24431-Scrub-pulling-tractors
Cheers.
I see a fair few dots there, but you're still a bit lousy with those commas and white space. (he grins)
Good post and I agree with you completely although I have never driven the modern stuff. I believe your comparisons in size of 8 versus 6 are valid going back to year dot.
Did you see the pictures of our 1965 scrub nines here . . . . . . https://www.heavyequipmentforums.com/showthread.php?24431-Scrub-pulling-tractors
Cheers.
Thanks scrub I had a look at those photos yea the gear I started on wasn't much newer than that.
I had upgraded hydroliks and pilot moters had the electric motors on them but not much different.
The first 6 months I was wondering what the hell I had gotten into,what a learning curve now days I call it the learning curve from hell.
The old bloke trying to teach me nearly went mad and every time I slingshot the drive I owed him a beer ( he drank a lot 4 a while ).
But what an adventure and looking back what an experience 4 a young bloke,funny I ran into the old feller the outher day
And I cannot thank him enough 4 having the patience to teach me.
He got his revenge but now Ime the one pulling my hair out trying to teach someone else and he thinks it **** funny
I had upgraded hydroliks and pilot moters had the electric motors on them but not much different.
The first 6 months I was wondering what the hell I had gotten into,what a learning curve now days I call it the learning curve from hell.
The old bloke trying to teach me nearly went mad and every time I slingshot the drive I owed him a beer ( he drank a lot 4 a while ).
But what an adventure and looking back what an experience 4 a young bloke,funny I ran into the old feller the outher day
And I cannot thank him enough 4 having the patience to teach me.
He got his revenge but now Ime the one pulling my hair out trying to teach someone else and he thinks it **** funny
You state you already have a D8K.Is it worth spending a lot of money on a dealer certified rebuild or a very good fitter?.
I have wondered wether a low houred ex military K with a modular aircon' cab would do the trick.It would be considerably cheaper than a new 8T and there aren't any electrics.It will allways sell for good money and with the aircon modular cab,it wouldn't be too hard on the operator.You are a lucky chap to be able to afford a new 8T and if I could afford one,I would buy one!!!however,I could stand sitting idle a £100k cert rebuild 8K but couldn't stand sitting a £400k 8T if work went quiet.
I have wondered wether a low houred ex military K with a modular aircon' cab would do the trick.It would be considerably cheaper than a new 8T and there aren't any electrics.It will allways sell for good money and with the aircon modular cab,it wouldn't be too hard on the operator.You are a lucky chap to be able to afford a new 8T and if I could afford one,I would buy one!!!however,I could stand sitting idle a £100k cert rebuild 8K but couldn't stand sitting a £400k 8T if work went quiet.
DMiller
Senior Member
Scrub, cam, always a pleasure and a delight to read the 'Queensland English' as you gents get on the posts. Can be a little disconcerting to define some of the slang but fun too! Almost as odd sounding to us yanks as our slang is to you.
DaMiller thanks mate and yes sometimes the lingo can b a challenge,keeps us thinking but.
Nicky has a good point if it were my money I'd get a d8r series 2 and keep the k as a mate 4 it.
Then aim 4 a second d6 then u have a pair of each competitive pricing and versatility is a tool most usefull.
Think about it.
Hey Blackearth u wanna weigh in here and tell us wat u think.
Nicky has a good point if it were my money I'd get a d8r series 2 and keep the k as a mate 4 it.
Then aim 4 a second d6 then u have a pair of each competitive pricing and versatility is a tool most usefull.
Think about it.
Hey Blackearth u wanna weigh in here and tell us wat u think.
Dozerbill63
Well-Known Member
They do nave thier own tous
You are right Old dirt , I would advise him not too over spend , things can go sour .