1974 D5 Crawler Problem

[JimHam]

The left track on my 1974 D5 has started "chattering" and and you can actually see it happening if you watch it while going forward. It's intermittent and Usually happens when moving forward on a downhill Slope. Its worse when the track gets loose. If I tighten that track it cuts down on it happening but I have to keep that side noticeably tighter to avoid it. It's not jumping sprocket teeth, its much finer than that. Feels to me like there are some splines somewhere in the left drive line that are slipping. When it starts I can reverse and that will stop it for a while. The problem has been getting progressively worse and I expect it will reach a point where I won't be able to use the dozer. Anybody have a similar experience or know what might be causing it? I suspect a worn bearing that allows too much play and lets something slip.

 

[dpendzic]

I would start by getting the track off the bottom rollers and checking them for vertical play. then i would drain the left final drive and pay close attention to metal in the oil---lastly check the sprocket bearings by prying vertically and horizontally on the sprocket

 

[Billy NY]

Quick thing you can do is remove the final drive oil fill cap, dip a magnet down in there and see what comes up, aside from what was mentioned below, sounds like something is failing in the final drive.

 

[JimHam]

Thanks for the input. I'm hoping it's something external and not the final drive. The local service guy I use called back and says he'll be up this way next week and will come by and look at it.

If it's the final drive I'll probably work it till it dies and sell it for scrap. Its been a good old machine and has held together long enough that I got more work value than what I paid for it. Hope its fixable though cause I have a long list of projects I'd like to complete. This old reclaimed mine land I own needs lots of work and it takes a dozer to do it.

 

[Billy NY]

Ran a lot of that era D5 tractors, they are very good tractors, worth repairing if the remainder of the tractor is in good condition. How is the undercarriage on it ? Worst is splitting the track and getting someone with the puller to remove and replace the sprocket, however, on these I think you can remove the entire component and have that work done off site. Been a long time since I was involved to that level of disassembly, last was a D6D all the way down to the internals of the bevel gear compartment, don't quote me, bit worth a little research. You'll just increase and accelerate the damage if you run til destruction insuring you'll need to replace it. Get a telescoping magnet, dip it to the bottom of the housing, see what comes up, that will tell you right away, that and if the sprocket is loose, also easy to check like described below.

 

[Tony016417]

Don't want to hijack this post but I just
bought a 1970 d5 cat and the "biscuits"
broke driving down the driveway the
rubber bushings between the crank shaft
and trans but can't find replacement
parts please help

 

[dpendzic]

try here

Florin Tractor
Sacramento,CA
www.florintractor.com
Dana at (916)383-0317 (800)223-9916

 

[Billy NY]

I experienced this numerous times on a 1970 955, L if I recall. You will want to make sure the engine alignment is correct, that is what kept causing these to fail after an out of frame overhaul. I believe there were shims involved. Was a long time back, but I would suggest making sure per the repair manual, alignment is good. Not sure if just radial, axial, or both, was too long ago.
Maybe the age of them was the cause, but there definitely can be an underlying cause.

 

[Britman]

This sounds like the splines on the sprocket hub are slipping. The splines are part of the bull gear in the final drive casing which may mean tearing down the final drive.