Best older D8??

[Phil]

Even if the older Cat D8 were not the 'best' older machine of that size, the supply of aftermarket parts available for it, makes the decision for you. The first 46A D8H had a fuel torque and a 6 roller frame, up until about serial #3,000. Also the earlier D8H was a low horse model, and had a different cylinder block and crankshaft I believe. The crank bearings were thicker and deemed not as efficient at heat transfer, when the horsepower went up, around serial #46A 11,000 or so. If the engine breather mounts on an angle then it is a high horse engine.

The difference between the low and high horse D8H is really noticeable. The final drives and the head gaskets as I remember, became the weaker link in the chain as the HP went up. I have great respect for someone out there repairing those final drives. I have heard of slightly bent final drive shafts causing short final drive life, and ripping frozen ground was not good for them either. The late D8H or the D8K with spacer plate engine, will always be one of Cat's best I think. Phil

 

[Arabhacks]

Uk?

Hello.

In the USA, in Texas at least, an operator can run a dozer, or not, no "licence" of any sort.
What are the requirements the other side of the pond?

 

[AmerIndependent]

If you are a tranny guy, who is the final drive connoisseur? A guy from the UK responded about the final drive repair, but was that US dollars? and was it just labor? parts? or what? Tell me more about the Italian parts and the cost differential of the parts. I'm interested.

Since the final drive is not a removable component, you must rely on local mechanics for that repair and it does require some special tooling. The best we can do in this situation is help with parts, just need to know specifically what you need.

 

[JASON M]

Since the final drive is not a removable component, you must rely on local mechanics for that repair and it does require some special tooling. The best we can do in this situation is help with parts, just need to know specifically what you need.

......... just ck'd it out (parts inventory)...... thanks. I've got a pretty good bunch of old-school mechanics working in my shop to handle the finals on the older D8's; worked on the D7F countless times.

 

[BC BOY]

pretty hard to go wrong either way, so long as they,ve been looked after. I,d definatley hang a ripper on the back for ballance plus its sure handy for ripping the roots on big stumps.

 

[tctractors]

If you Put out to buy a D8K make sure its fitted with a K blade (3x7 bolt sections on the cutting edge) at about Ser No 4200 Cat altered the angle of the cutting edge to blade form, this made the Blade a most effective piece of Iron, it was possible if you were an 1" high to cut off a 1/2" to see how it looks, the K blade to a H blade was a big improvement.
Sadly the D8K still make some very big prices as there is still a very good demand for these tractors on a World wide scale, so try to buy from a private sale if possible, parts wise their is realy no problems, if CAT cannot supply it, other outlets will not struggle to meet your requirments, saying that a Manual G/box in a K could be a tricky beast I believe.

best of luck (you might need it)
tctractors

 

[DPete]

Found these of 77V18843 I owned it for 10 years. Gone now though, exhaust was changed when I got it, never put the laydown back on. Testing my new puter at the same time. Windows 7 rocks

 

[2stickbill]

pretty hard to go wrong either way, so long as they,ve been looked after. I,d definatley hang a ripper on the back for ballance plus its sure handy for ripping the roots on big stumps.

Might be better to put a good winch on it.Louisiana has a few wet spots.

 

[Dozerboy]

X2 thats what I was getting at I know a D8 wouldn't last 1 rain here or at any day even during the dry season in southern LA.

 

[JASON M]

Well, I made the decision. Bought a D8H w/ a 3 shank, 4 bbl ripper-rack. Price was too good to pass up; all the gauges operable and pegging the green arcs. Very late model serial # Higher- horse Motor sounded strong, much like my D9G...Very straight metal. Huge U-blade, (10,000 lbs, I think) good cutting edges, smooth shifting transmission that seemed to pick up its pressure well and no evidence of leaks, except at the cylinder packs and he's going to give 'em all a re-packing before shipping. Only downside is the rails are worn (65% remaining), sprockets are shot and the grousers are thin, but will last till the next set of rails are installed...... that'll probably be years from now. Just can't wait to put her in the dirt! Thanks for the help, D8H/K gurus.

BTW: Further research indicates that a few of the D8H's, maybe the last 2000 manufactured utilized the pinned equalizer bar arrangement, tying the track frames together. Anybody know if that is a valid improvement? or just a change, like the elevated sprocket, high drive machines?

 

[JASON M]

One more question. Where is the weight on the D8K vs the D8H. I can't seem to find the extra 10,000 + lbs in a comparable D8K; It must be hiding in there somewhere.

 

[Greg]

Were there actually more D8K's built than D8H's? I thought that the H's were the highest number as it was built for I believe 12 years? Somebody please correct me if I am wrong.

 

[DPete]

Were there actually more D8K's built than D8H's? I thought that the H's were the highest number as it was built for I believe 12 years? Somebody please correct me if I am wrong.

You are correct, D8H 46A to serial # 34086 - D8K 77V to #18848

 

[JDOFMEMI]

One more question. Where is the weight on the D8K vs the D8H. I can't seem to find the extra 10,000 + lbs in a comparable D8K; It must be hiding in there somewhere.

Jason

I could be wrong, but if you are looking at operating weights in the cat performance handbook, I believe the weight listed for the H is for a tractor with an "S" blade and a drawbar, while the weight listed for the K includes a multishank ripper with one shank. That would explain the "missing" 10,000#

If I remember correctly, the D-8K's we had were about 2-3,000# heavier than the H, and they were each comperably equipped.

 

[JASON M]

Y'all sure 'bout the production #' of the 8K vs the 8H........? As long as I can get parts, it's not a deal breaker.


So, I guess, Jerry, that the (2) machines are very comparable, weight-wise? I sure hope they are. A 4-bbl ripper rack is worth 8,000 lbs and I think your analogy is correct. That could be.

 

[2stickbill]

Y'all sure 'bout the production #' of the 8K vs the 8H........? As long as I can get parts, it's not a deal breaker.


So, I guess, Jerry, that the (2) machines are very comparable, weight-wise? I sure hope they are. A 4-bbl ripper rack is worth 8,000 lbs and I think your analogy is correct. That could be.

You can get parts for them and older machines.The K had more HP used more fuel but give faster production faster.

 

[AmerIndependent]

Jason M,

This is a pretty good site for weight and miscellaneous Cat information: http://www.ironrecord.com/

I looked at the weight difference between the D8K and D8H and it's showing closer to 20,000 lbs difference depending on serial #. I don't know if it's correct or not. You might want to check it out for yourself, it's got some good information on there.

Congrats on your purchase by the way!

 

[JASON M]

These eqt wts are starting to get to me. I've got a D9G (66A) with an inside C-frame, push-cushion blade (CU type) and the factory rear counterweights installed. The Cat Perf Handbook lists the weight at 68,500 lbs. When I bought it years ago, I remember telling my lowboy driver to just go pick it up, no big deal. After he got his triple-axle detach under it, binded it down, and started lugging on it, he knew something amiss. He called me via cell ph and told me that the load was much more than 68,000 lbs and wanted to stop at a set of Cat scales at a truck stop and ck it. I remember him telling me "a little over 90,000 lbs"...............
So, just because I'm interested today, and not very busy right now, I weighed the dozer on my "in-house" 100,000 lb scale. It weighed 94,000 lbs, exactly. It is apparent that Caterpillar issued that weight by tractor only; no blade and no rear attachment. So, I am deducing that the front blade weight at about 10,000 lbs and the rear counterweights at the difference.... in this case.... about 15,000 lbs. I think this is how they (Cat) arrived at their published #'s.
Now, I also weighed my Cat D6R LGP series II, w/ rear Paccar 56 winch installed. It weighed a cool 53,000 lbs. The book weights according to Ironclad, include the ser # prefix, in this case, mine was prefixed ADE. Well that narrows the machine identification. They give the base weight at 45,600 lbs. The Cat Perf handbook lists the weight of the Paccar 56 winch at 3600 lbs, w/ cable on the drum, making a combined weight of 49,200 lbs total machine weight........... still not close enough for me.
Anybody know for sure, how eqt weights are arrived? As far as I'm concerned, the only way to get closer than a 10% weight estimate is by weighing the machine yourself.

 

[AmerIndependent]

I have no idea where those weights are derived from but since we don't have a 100,000 lbs capacity scale, we've always trusted the websites.

Though we may never know where they come up with the weights, because of Jason M, we will now know they are not accurate. Haha. Thank you good sir for your efforts! :salute

 

[JASON M]

Well, you are welcome. I'm the son of (3) generations of Professional Engineers; but I'm not an engineer. Anyway, it was always taught to me that "Everything can be explained".......... that is the root of my curiosity.

Now, I'm really interested in weighing the old Cat D8H w/ the ripper-rack and Full-U blade, when it gets here next week. I'll report back its exact weight too. I've always subscribed to weight and horsepower to get the job done..... Now we're going to try to measure it; at least the weight of it. I don't have a dyno for the horsepower; we'll just have to see how she spins the tracks in 2nd gear.