Hydraulic Pump - TC55DA EHSS

99k1500 · 2026-02-04T10:16:47-0500

I am going to start this as a new thread with more details, as I have a feeling more people with these tractors or pumps are going to need details.
Originally I piggy backed on another thread - But this is now about more than just a leak.
www.tractorbynet.com/forums/threads/tc55da-hydraulic-leak.138470/

The pump on these units is no longer in production and currently there is not a substitute.
Pump part number SBA340451161
This pump was used on the EHSS models of
Case / New Holland Tractor Boomer 4055 / Boomer 4060 / DX48SSS / DX55 / DX55EHSS / DX55SSS / DX60 / FARMALL 55 / FARMALL 60 / T2410 / T2420 / T2520 / TC48DA / TC55DA
I "believe" it was made by kayaba as an OEM part

In my case the case housing cracked during a cold weather startup. I believe that is the case for another member in PA.

I have a couple of people working on a remanufactured or aftermarket pump, but they don't seem to be available. There is hope that a company is developing one or at least that was referenced in the original thread.

This is a dual pump / tandem. I am in the process of working with a machine shop to try do duplicate the front end of the housing.

Here is a picture of the crack at the front of the housing as well as a screenshot of a slow motion video I took on startup - showing the fluid rushing out of the crack.

screenshot of slow motion video - Leak.jpg

99k1500 · 2026-02-04T10:21:26-0500

Here is a stolen image from the internet ( stock photo ) The crack is under the companies logo on the portion of the housing.

nyone · 2026-02-04T10:54:35-0500

Why does it cracked with cold start up? What does each section of the pump do? Could it just be made into a single pump?

oldnslo · 2026-02-04T11:14:49-0500

Typically pump housings cracking is from over pressure or pressure spikes. Cold oil could have or may have caused an over pressure condition.

99k
What is the mounting pilot diameter, drive shaft dimensions, mtg bolt pattern, displacement? With this information you might be able to find a pump that will bolt up but most likely the ports will be in different locations and possibly different sizes.

It is also possible that an OEM pump manufacturer made a custom shaft so you were forced to buy from New Holland.

99k1500 · 2026-02-04T13:40:36-0500

FWIW,

I have no specs on the output of this device, but since these tractors are EHSS, I am unwilling to mess with the specs too much.
Currently working on this is:

NewHolland of Tulsa
TractorPartsASAP ( all states ag parts ) says they do not have an alternative - they looped in Precision Fluid Power out of OKC - They say they are working on alternative pumps / adapters
Contacting PeriParts out of NJ stated there is no known replacement.
I have contacted the TWO entities that say online they have a pump... Both indicate it is out of stock - one of these came from researching on TractorHouse

( from the other thread ) User cj7jeep187 out of PA has been working on it as he has the exact same issue last week.

I spoke with a used parts group out of central PA that told me they’re working with an aftermarket manufacturer that may actually have a reproduction version available in the next month or so. They’re going to call me when they know more and I’ll post here. I’m also looking at local fab guys/hydraulic shops that can try to repair since I’ll probably pick up a replacement anyway.

oldnslo · 2026-02-04T15:22:00-0500

I am not sure how the EHSS interfaces with the pump but wish you the very best in finding an alternate solution.

99k1500 · 2026-02-04T15:26:50-0500

I am not sure either, but it is not a normal clutch it is an inching pedal and an electronically controlled hydraulic shift. I do know all of the EHSS units utilize a different pump than the standard units.

EHSS (Electronic Hydraulic Shuttle Shift) transmission is a, often found in New Holland tractors, that allows operators to change between forward and reverse gears without clutching. It uses hydraulic clutches for smooth, fast directional changes, improving efficiency in tasks like loader work. It is often distinguished from fully manual or fully hydrostatic systems.

toot77 · 2026-02-04T17:23:39-0500

Does the pump have a manufacturers model & serial plate on it? Even though it is likely a special for New Holland, the oe manufacturer's number may provide some information to help to reverse engineer a solution . If it is KYB, I am attaching a KYB hydraulics catalog link that I found.

https://www.kyb.co.jp/english/media/hydraulics_products_guide_en.pdf

There is also a phone number on the back page in case you have not contacted KYB yet.

Good Luck

99k1500 · 2026-02-04T18:39:37-0500

It is KYB

35-17CE
KPN05
Aztec Replacement for Kayaba KPN05-35-17CE

99k1500 · 2026-02-04T18:42:58-0500

toot77 said:
Does the pump have a manufacturers model & serial plate on it? Even though it is likely a special for New Holland, the oe manufacturer's number may provide some information to help to reverse engineer a solution . If it is KYB, I am attaching a KYB hydraulics catalog link that I found.

https://www.kyb.co.jp/english/media/hydraulics_products_guide_en.pdf

There is also a phone number on the back page in case you have not contacted KYB yet.

Good Luck

Thank you! It is a lead.... I had found that same document.... But just got the pump off today. I have reached out to AZTEC
*The original pump is obsolete and no longer supported from Kayaba and CNH. This is a custom-built aftermarket replacement that matches the performance but may be larger than the original pump.

Sportsman762 · 2026-02-04T18:47:19-0500

@99k1500 sorry to hear about your troubles. This pump is a challenging one to find information on.
It fits New Holland: Boomer 1055, Boomer 4060, T2410, T2420, TC48DA, TC55DA. Case IH DX48, DX55, DX60, Farmall 55, Farmall 60.