So a few questions...I have a D8k that caught fire in the spring. I have been looking into it...as well as I just looked at a d8h yesterday. The H is in very good shape.... but as it warmed up .. it wouldnt turn left anymore. I pulled the lever and pushed the brake all the way and it just kept going straight. Is it the steering clutch? Brake...? There is also another H that has a bad final drive. Are final parts from A 8K be able to fit on a 8H ?
-
Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!
D8 H and D8K Final Drive
- Thread starter tkfarms
- Start date
Nige
Senior Member
Without Serial Numbers it's impossible to answer your question.
Ok... might be able to get those...What about the first question?
Nige
Senior Member
Not my area of extpertise TBH. Needs someone with recent experience of these old dinosaurs.
If you want some documentation regarding System Operation plus Test & Adjust for the D8H you will need to supply a Serial Number.
Last edited:
Check Break
Senior Member
Like Nige said, you need serial numbers and parts manuals. The H will accept a brake upgrade, from 18xxx forward from memory. I don't remember if all the Ks used the same brake or if the K-s upgraded again around 77v4xxx (76v a much lower number). Best guess is you can upgrade as mentioned, the late H and early K are similar, but only the parts book will know. Ebay is your friend. There's usually useable manuals at reasonable prices. The creampuffs will cost you a bit more.
Shop Dweller
Well-Known Member
- Joined
- Jul 26, 2024
- Messages
- 104
- Location
- NW, North Carolina
- Occupation
- Semi Retired from 28 years logging, now I wrench and weld Heavy Equipment
There is a guy here locally that used to have a pretty big grading company. Big enough they built sections of US Highway. But he still did custom grading for homeowners as well, cleared land, etc. He had bunches of 8H and 8K dozers. Lots of people swear by the H, but he always said everytime they stumped or got in rock with the H models they lost a final or two. He said he preferred the K models by far due to that one issue with the H models. He probably had 20 of each over the years.
Shop Dweller
Well-Known Member
- Joined
- Jul 26, 2024
- Messages
- 104
- Location
- NW, North Carolina
- Occupation
- Semi Retired from 28 years logging, now I wrench and weld Heavy Equipment
He had a shop that employeed 3 guys all the time. His head guy was as good a Cat man as there has ever been. He was certified by Cat to do warranty work even though he didn't work for Cat. I think he did originally. I can build a final and it will last years in something like my 90s D6D machine, even with much abuse. And I can build a final drive in my early 60s D6C which is straight drive and turbo with tons of power, and it will last for years. But if I want to I can probably tear one out of the 6C about anytime I want to in rough conditions. Early Cats just had weak finals across the board. I think it had more to do with that than the mechanic. Lots of those were fixed by Cat mechanics, because they worked in several states.
Thanks for all the reply's!~ Love reading all the posts about the old cats we have and what not. Learn something new everyday. The reason I asked about the interchangable parts is because there is another 8h thats for sale, but the right hand final is toast. I have actually 2 parts D8K cats now and not sure what to do yet. The one k had a bad motor... and now my original 8k burnt... but Im not sure yet how bad... still have to go through it.....I was even thinking... if I bought the D8h with the bad final in it, repair it with parts from my k ... or even swap the D342 to the 8k ??
Shop Dweller
Well-Known Member
- Joined
- Jul 26, 2024
- Messages
- 104
- Location
- NW, North Carolina
- Occupation
- Semi Retired from 28 years logging, now I wrench and weld Heavy Equipment
I am not real familiar with the D8's personally but im fairly certain the finals won't interchange. There is an old thread I saw here once with people debating the differences. It was several pages long.
Nige
Senior Member
Quote some Serial Numbers and you might get some answers. My crystal ball is in the shop for maintenance at the moment.
I was under the impression that one of the biggest changes was the heavier final drives on the K series. The low horse H’s were ok but when they cranked up the power on the high horse H’s, they encountered some durability issues. I may be wrong but i seem to remember it that way.
Be a week or two before I go see the machine...but Ill get em.!!
And from reading a lot of posts on this site....some people have said the extra hp (300) In the K machines was hard on the finals?
tctractors
Senior Member
I could rattle on for hours about D8 Final Drives from the first Series H through to the end of the flat drive D8K's, this year I have only rebuilt 4 final drives on D8's, my record is 5 in 2 weeks but they are now in low numbers here in the U.K. still working, although I have 2 full hit engine rebuilds (D342) on the go at the moment, the big changes within the drives are - the outer bearing size in the preload cap, it was smaller than the other 2 taper bearings being changed to all 3 outer bearings being the same, the Dead shaft was changed for a bigger better item with a larger inboard bearing and housing, the duo'cone seating changed from an alloy mounting to a machined area in steel, the tin seal guards changed to again a machined steel type, the intermediate 1 piece gear changed to a 2 section gear held in place by a wire snap ring, there are lots of other small changes but without Serial numbers it's hard / impossible to give you any true facts on your question other than I have fitted D8K F/Drives into a D8H, the outer hub C type collars on a K have 4 bolt mounting, on a D8H they have only 2 bolts, when setting these collars down you have the shims in your left hand and the hub key goes to your right hand on both sides, the outer cap has large lumps 180 deg' on the outer face they line up with the split joint between the frame and the C collar with the chamfer facing forward, I would have rebuilt over the years many of the drives and have photos of 78 of them, on your turning fault you would have to check firstly the brake adjustment then if needed a pressure test that is simple to do but is this D/D or P/Shift.
TK Farms,are you the gent with the D8K on Youtube over in Canada?
I saw it catch fire when you were pushing scrub up with it.
I hope you get it fixed up.
As for final drive repairs on D8’s ,I can assure you from experience on my own D8’s that TC tractors is the man to advise you on what is interchangeable on D8’s and what isn’t .
I saw it catch fire when you were pushing scrub up with it.
I hope you get it fixed up.
As for final drive repairs on D8’s ,I can assure you from experience on my own D8’s that TC tractors is the man to advise you on what is interchangeable on D8’s and what isn’t .
tctractors
Senior Member
I have posted many pictures of D8 f/drives in bits in Shop Talk.
Yes That Is Me.
Nice... I will go check that out!!