Not sure what CAT was using for wet brake linings back in the day, though they had to be same/similar to the wet clutch linings that preceded them. Those wet clutches were filled with engine oils and earned a reputation for durability unmatched by anyone else in the industry. I would bet they still are most commonly filled with modern motor oils today without any problems.That was manual clutches, power shift transmissions seem to be another animal altogether!

I am most familiar with JD products with their famous/infamous 8 speed power shift transmission and power actuated wet brakes. In the early 1960’s JD had to do the same education with their new owners that Eddie referred to earlier. The most noticeable result of using an engine or hydraulic oil in a JD tractor was brake noise and chatter. As soon as the customer complained to the dealership about their new tractor making bad noises when the brakes were applied, the mechanic could be certain that the owner had replaced the “303” fluid with something else. Usually the noise was objectionable enough that the owner would quickly start using the correct fluid such that those tractors with the optional power shift transmission, rarely experienced failure as a result of the wrong fluid being used.

Today (and for the last 40 years or so) the “303” fluid is unavailable because of the lack of whale oil additive and other material is used to formulate fluids to the current spec. When you see a bucket of fluid for half price and it says on the side it meets the same standard as 303, it’s a sign that you should “run Forrest run”. That being said I believe those “yellow bucket” oils as they are called here are probably better than the motor oils that were specified for CAT oil clutches back in the 1950’s and 60’s. They are in no way comparable to JD HYGARD, CaseIH HYTRAN or CAT TO-4!

Today in the “asbestos free” world we live in, JD wet brake linings have been redesigned from a thick section that was attached by countersunk brass rivets to a bonded lining material similar to that used in the power shift transmission disks and brakes. These linings seem to be much more sensitive to the ill effects of moisture in the fluid and the resulting corrosion/damage than the old riveted linings ever were.

I was “lucky” enough to replace brakes on 4 tractors a couple years ago and in a couple of them found intact bonded linings that could be easily peeled away from the backing plate with a thumbnail. There seemed to be a fine layer of rust between the lining and backing plate I assume was due to moisture being absorbed by the lining or possibly the oil additive package attacking the adhesive directly.

All in all a good example of the cost of using cheap fluids!

So I got the brake bands re-lined and the steering clutches reinstalled in the machine. Tomorrow or the next day I will be ready to dump fluid back in. I pumped all the old fluid out into jugs with the intent of probably reusing it. Then I got to wondering if I should replace it. I wasn't necessarily having any trouble other than the brake linings crumbling, which it sounds like isn't really that uncommon, but wondering if I should consider replacing with new oil anyway. The original manuals all specify motor oil but surely there's something better by 2020. I mean, that was almost 50 years ago!

What's best to put back in a powershift with wet brakes?

Hi,
any oils that meet the TDTO4 specification that Cat specify should be fine. See ACMOC discussion here on this link :-

www.acmoc.org/bb/archive/index.php/t-10401.html

Cheers,
Eddie B.

"edb" wrote:

Hi,
any oils that meet the TDTO4 specification that Cat specify should be fine. See ACMOC discussion here on this link :-

www.acmoc.org/bb/archive/index.php/t-10401.html

Cheers,
Eddie B.

Thank you. I did a search for drive train oils and found the one you referenced among others. And it seems after reading them I was more confused than ever. Which that's nothing new when doing research on forums.

I'll attempt to summarize my opinion based on the threads I read:

My tractor calls for SAE30 engine oil in the rearend/transmission.
At some point, motor oils changed to the point of being a bit too slippery for wet clutches (more zinc I think, ZDDP?)
Then as the govt pushed to reduce zinc, motor oil became ok again?
As combination tractor drive train/hydraulic oils became the recommendation, Cat came out with TO-2 for rearend/powershift transmission usage
Cat rev'd up their TDT oil to TO-4 for newer organic clutches, however it's backward compatible to the TO-2 requirements

Sooo, it seems a TO-2 (obsolete) or TO-4 or equivalent should be fine in my rearend, bevel housing, steering clutches and transmission. I know it already had several gallons of CIH HyTran in it as it was low when I got it and that's what I had on hand and used it.

I was planning to use my old oil after the brake job as I had pumped it out into clean buckets. But after further review, I don't particularly care for how dark it is and the black sediment that's settling out in the bottom of the buckets is gritty, presumably brake lining material.

I called Cat yesterday and 5gal buckets of TDTO are $81, 55gal drum is $821. I have used HyTran in my tractors for years but was getting tired of paying $105 a bucket for it so just recently bought some Shell Rotella HD drivetrain oil which I noticed also lists TO-2 on the label. I had made a good purchase on it at $40 a bucket (normally $60) so I am seriously considering using it if I can get some more of it right.

If I'm missing something horribly here, please nobody be afraid to jump in and straighten me out.