stabber
Active Member
Please help me diagnose the root cause of my CAT D8L transmission overheating issue:
Equipment Specs:
Caterpillar D8L SN:53Y02410
Backstory:
With all the rain we had in OK, most of my lower most productive farmland was flooded and debris covered. In a last ditch effort to "save" the ranch I decided to splurge and get the best condition D8 size dozer I could afford and give it one last go. I did a tremendous amount of research and determined the best option for us would be a low hour CAT D8L (all mechanical, great reputation etc). I found a machine about 8 hours from me with about 3k hours on a certified engine, torque converter and transmission (about 12,400 frame hours). After speaking with the owner and his mechanic I felt comfortable that it was a good machine and bought it.
I literally cried as I drove the dozer off the truck and watched the transmission temperature creep up and after walking the dozer about 1/4 mile it was a hair from throwing on the powershift transmission light. I parked the dozer and so far have:
1. Power washed out the radiator external (removed a lot of debris toward the base)
a. Tested the radiator fluid (was great), but I flushed it and used 3 gallons of the CAT flushing fluid.
b. Tested the machine and engine stays pretty cool, but transmission temp creeps up to an unsafe level in about 1/2 hour with 85 degree ambient temperature
2. Changed transmission fluid all filters and screens (also had tested)
a. Filters and screens did not have any debris
b. oil test: Silicon 18.01 PPM, Tin 0 ppm, Silver 0 PPM, Aluminum 2.06 PPM, Chromium 0.33 PPM, Lead 88.9 PPM, Copper 178.22 PPM, Nickel 0.111 PPM, Iron 252.51 PPM (Maybe pump issue???)
3. Cleaned all break linkages and parked on hill (seems to roll ok in neutral) (forward and reverse)
4. Things that I have bought
a. All books (parts manual, maintenance, operator)
5. I spoke with former owner and mechanic - I suspect they knew something was up, but obviously swore that it worked great when it left (but they used it very little)
6. I bought a set of pressure gauges, but have yet to connect up and pressure test it
7. Dozer has a ton of power and transmission shifts in all gears and drives true, clutches and breaks work as per specifications
I really don't have that much time or money, I tried to have CAT come out, but its not close to the dealer and they are booked up with all the big guys .... I work the ranch mostly on weekends with my 6 and 8 year old boys. I do have access to a rebuilt transmission pump and possibly the scavenger pump (I don't know where this is located though?). How hard is it to change out the pump? can I do it myself? The book is a bit lacking in details, is there anything I need to look out for? Do the pumps need to be primed?
Equipment Specs:
Caterpillar D8L SN:53Y02410
Backstory:
With all the rain we had in OK, most of my lower most productive farmland was flooded and debris covered. In a last ditch effort to "save" the ranch I decided to splurge and get the best condition D8 size dozer I could afford and give it one last go. I did a tremendous amount of research and determined the best option for us would be a low hour CAT D8L (all mechanical, great reputation etc). I found a machine about 8 hours from me with about 3k hours on a certified engine, torque converter and transmission (about 12,400 frame hours). After speaking with the owner and his mechanic I felt comfortable that it was a good machine and bought it.
I literally cried as I drove the dozer off the truck and watched the transmission temperature creep up and after walking the dozer about 1/4 mile it was a hair from throwing on the powershift transmission light. I parked the dozer and so far have:
1. Power washed out the radiator external (removed a lot of debris toward the base)
a. Tested the radiator fluid (was great), but I flushed it and used 3 gallons of the CAT flushing fluid.
b. Tested the machine and engine stays pretty cool, but transmission temp creeps up to an unsafe level in about 1/2 hour with 85 degree ambient temperature
2. Changed transmission fluid all filters and screens (also had tested)
a. Filters and screens did not have any debris
b. oil test: Silicon 18.01 PPM, Tin 0 ppm, Silver 0 PPM, Aluminum 2.06 PPM, Chromium 0.33 PPM, Lead 88.9 PPM, Copper 178.22 PPM, Nickel 0.111 PPM, Iron 252.51 PPM (Maybe pump issue???)
3. Cleaned all break linkages and parked on hill (seems to roll ok in neutral) (forward and reverse)
4. Things that I have bought
a. All books (parts manual, maintenance, operator)
5. I spoke with former owner and mechanic - I suspect they knew something was up, but obviously swore that it worked great when it left (but they used it very little)
6. I bought a set of pressure gauges, but have yet to connect up and pressure test it
7. Dozer has a ton of power and transmission shifts in all gears and drives true, clutches and breaks work as per specifications
I really don't have that much time or money, I tried to have CAT come out, but its not close to the dealer and they are booked up with all the big guys .... I work the ranch mostly on weekends with my 6 and 8 year old boys. I do have access to a rebuilt transmission pump and possibly the scavenger pump (I don't know where this is located though?). How hard is it to change out the pump? can I do it myself? The book is a bit lacking in details, is there anything I need to look out for? Do the pumps need to be primed?
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