Descrizione
This page covers two reference model numbers — TF1204.551.1 and TF1304.55.012 — that share the same core specification: 100 mm bore, 40 mm rod, 200 mm stroke, and 535 mm mounting distance. Both are tractor hydraulic lift cylinders supplied by Ever-Power for agricultural lift applications in the large-frame 535 mm mounting platform.
The 100 mm bore places these cylinders at the upper-middle of the 535 mm mounting group — generating approximately 24% more theoretical extension force than the TF1004.55.8 (90 mm bore) at the same pressure, and approximately 21% less than the TC2104.55JD.010 (110 mm bore). The 40 mm rod is the heaviest rod specification in the 200 mm stroke subgroup, proportioned to suit the higher force loads that a 100 mm bore cylinder handles.
Ever-Power supplies both TF1204.551.1 and TF1304.55.012 as aftermarket replacement cylinders. If your existing cylinder carries one of these reference numbers, confirm the bore, rod, stroke, and mounting distance match — and note the specific reference number in your inquiry so the correct variant can be confirmed.
Why TF1204.551.1 and TF1304.55.012 share this page
Both reference numbers correspond to the same physical specification: 100 mm bore, 40 mm rod, 200 mm stroke, 535 mm mounting distance. In agricultural hydraulic cylinder cataloging, different reference numbers with the same core geometry typically indicate application variants — such as differences in the mounting end connection, port thread specification, or a designation from a specific OEM parts list. Creating two separate pages with identical dimensional content would not serve a buyer trying to understand the product or confirm a replacement. Where dimensions are confirmed identical, one page covering both references — and directing buyers to specify which number they hold — gives more useful information than two near-duplicate pages.
TF1204 / TF1304 — Technical Specifications
| Parameter | Value | Notes |
|---|---|---|
| Reference Models | TF1204.551.1 / TF1304.55.012 | Same core specification; specify reference number in inquiry |
| Bore Diameter | 100 mm | ~24% more piston area than 90 mm bore; only 100 mm bore in the 535 mm / 200 mm subgroup |
| Rod Diameter | 40 mm | Heaviest rod in the 200 mm stroke subgroup; rod-to-bore ratio 0.40 |
| Stroke | 200 mm | Same as FT800.55A.012 and TF1004.55.8 |
| Mounting Distance | 535 mm | Shared with FT800, TF1004, TC2104, FS2604; pin-center to pin-center retracted |
| Extended Length | 735 mm | Pin-center to pin-center at full extension (535 + 200) |
| Applicazione | Agricultural tractor hydraulic lift systems | Specify reference number; confirm bore — unique identifier in the 535 mm / 200 mm subgroup |
| Supplier | Ever-Power | OEM and aftermarket supply; custom specifications on inquiry |
100 mm Bore in the 535 mm Platform: Position and Force Context
The 535 mm mounting group spans bore sizes from 80 mm to 120 mm. The TF1204/TF1304 at 100 mm bore sits at the midpoint of that range — both in terms of bore size and force output. The piston area at 100 mm bore is approximately 7,854 mm² (π × 50²).
| Model | Bore | Rod | Stroke | Piston Area | Force @ 160 bar |
|---|---|---|---|---|---|
| FT800.55A.012 | 80 mm | 32 mm | 200 mm | 5,027 mm² | ~80.4 kN |
| TF1004.55.8 | 90 mm | 35 mm | 200 mm | 6,362 mm² | ~101.8 kN |
| TF1204 / TF1304 | 100 mm | 40 mm | 200 mm | 7,854 mm² | ~125.7 kN |
| TC2104.55JD.010 | 110 mm | 45 mm | 180 mm | 9,503 mm² | ~152.1 kN |
| FS2604.55D4.010a | 120 mm | 60 mm | 180 mm | 11,310 mm² | ~181.4 kN |
Engineering Reference Note: All force figures are theoretical calculations based on bore geometry and 160 bar reference pressure. They are not rated product specifications. Actual output depends on the system’s operating pressure, valve restrictions, and circuit efficiency. No rated pressure for TF1204.551.1 or TF1304.55.012 has been confirmed by Ever-Power for publication here.
From 90 mm to 100 mm: The Force Step at the Midpoint of the Group
Moving from the TF1004.55.8’s 90 mm bore to the TF1204/TF1304’s 100 mm bore increases piston area from 6,362 mm² to 7,854 mm² — a 23.4% increase, close to the 26.6% step from 80 mm to 90 mm. Each 10 mm increment in bore produces a roughly similar percentage increase in force potential throughout this range, because bore area scales with the square of the radius and the increments are evenly spaced.
At 160 bar reference pressure, the theoretical force increases from approximately 101.8 kN (TF1004) to approximately 125.7 kN (TF1204/TF1304) — an additional 23.9 kN, or roughly 2.4 additional metric tonnes of linear force at the rod tip. A machine designed around the 100 mm bore cylinder is calibrated to use this force level through its lift linkage geometry, operating at a specific system pressure and pump output that matches the 100 mm bore’s area and flow requirements.
The fluid volume displaced per full extension cycle increases proportionally: at 100 mm bore, one full 200 mm stroke moves approximately 1,571 cm³ of fluid (7,854 mm² × 200 mm). That is about 24% more than the TF1004’s 1,272 cm³ per cycle, and approximately 56% more than the FT800’s 1,005 cm³. The hydraulic pump on a machine using the TF1204/TF1304 must supply this volume within the cycle time the operator expects for lift speed — which explains why larger bore cylinders require correspondingly higher-output pumps.
40 mm Rod: The Heaviest in the 200 mm Stroke Subgroup
At 40 mm, the rod on the TF1204/TF1304 is the largest diameter in the 200 mm stroke subgroup — 5 mm more than the TF1004.55.8’s 35 mm rod and 8 mm more than the FT800’s 32 mm rod. The rod-to-bore ratio is 40/100 = 0.40, matching the FT800’s ratio and slightly above the TF1004’s 0.39.
A 40 mm rod cross-section is approximately 1,257 mm² (π × 20²). The annular area available for retraction in a double-acting configuration is 7,854 − 1,257 = 6,597 mm². At 160 bar reference pressure, retraction force is approximately 105.6 kN — about 84% of extension force. The heavier rod reduces the retraction-to-extension force ratio slightly compared to a thinner rod, but this is a standard characteristic of all hydraulic cylinder designs and does not affect extension performance.
For buckling resistance, the 40 mm rod at 200 mm stroke has a meaningfully better slenderness ratio than the FT800’s 32 mm rod at the same stroke. The cross-sectional moment of inertia scales with the fourth power of the radius — a 40 mm rod has (20/16)⁴ = approximately 2.44 times the bending stiffness of a 32 mm rod. At the force levels a 100 mm bore cylinder generates, the heavier rod provides appropriate structural robustness for the axial and side loads the installation may impose.
From a replacement perspective: the 40 mm rod means pin diameters, clevis bore dimensions, and end-connection geometry will be larger than on lower-bore cylinders in this range. A 40 mm rod end will not fit a bracket designed for a 35 mm or 32 mm rod without modification. Confirm rod diameter and pin dimensions independently of bore measurement when sourcing a replacement.
TF1204.551.1 vs TF1304.55.012: What the Numbers Tell You
The two reference numbers — TF1204.551.1 and TF1304.55.012 — differ in their prefix codes (TF1204 vs TF1304) as well as their suffix notation (.551.1 vs .55.012). In most hydraulic cylinder part numbering systems used in the agricultural sector, a change in the full model designation — rather than just a suffix — typically indicates a distinct production variant or a different OEM application code, even when the core dimensional specification is identical.
Common reasons for two reference numbers covering the same physical specification include: the cylinder was listed under different part numbers in different machine models’ parts catalogues from the same manufacturer family; the reference number changed across a production revision while the cylinder geometry remained unchanged; or one reference number applies to a base model and the other to an application-specific variant with a minor difference in end connection or port specification that is not captured in the four primary dimensions.
What to do when your part carries one of these numbers:
Note the exact reference number from the existing cylinder or machine documentation and include it in the inquiry. Measure the bore (100 mm), rod (40 mm), stroke (200 mm), and mounting distance (535 mm) directly from the existing cylinder to confirm the physical specification matches. Also measure pin diameters and identify the end connection type — if TF1204.551.1 and TF1304.55.012 do differ in end-connection detail, those measurements will surface the difference. Providing both the reference number and the measured dimensions gives the most complete basis for confirming the correct replacement.
Identifying the TF1204/TF1304 Within the 535 mm Group
The three-step identification process used for the TF1004.55.8 applies here as well, with bore as the final identifier. At 100 mm bore, this is the only cylinder in the 535 mm / 200 mm stroke subgroup with that dimension.
| If your measurements show… | Then the model is… |
|---|---|
| 535 mm MD + 200 mm stroke + 80 mm bore | FT800.55A.012 |
| 535 mm MD + 200 mm stroke + 90 mm bore | TF1004.55.8 |
| 535 mm MD + 200 mm stroke + 100 mm bore | TF1204.551.1 / TF1304.55.012 |
| 535 mm MD + 180 mm stroke + 110 mm bore | TC2104.55JD.010 |
| 535 mm MD + 180 mm stroke + 120 mm bore | FS2604.55D4.010a |
Note that the two largest-bore cylinders in this group (TC2104 and FS2604) use 180 mm stroke rather than 200 mm — so stroke measurement also helps distinguish the large-bore group from the mid-bore group when mounting distance alone is confirmed. A 535 mm mounting distance with 180 mm stroke points to the 110 mm or 120 mm bore cylinders; 200 mm stroke points to the 80 mm, 90 mm, or 100 mm bore models.
Force Output and Hitch Lift Capacity: Keeping the Distinction Clear
At approximately 125.7 kN of theoretical extension force at 160 bar, the TF1204/TF1304 generates among the higher force outputs in this product range. This cylinder force — acting along the cylinder axis at the rod tip — is an input to the machine’s lift system. The rated hitch lift capacity of the tractor using this cylinder is the output of that system, incorporating the lift arm length, the mechanical advantage of the linkage, the angle of force application, and the structural efficiency of the mechanism.
A tractor using a 100 mm bore cylinder at its designed system pressure and with a well-maintained lift linkage will be capable of its rated lift capacity. If the machine is struggling to achieve rated lift with this cylinder installed and confirmed correct, the investigation should focus on hydraulic system pressure — whether the pump and relief valve are maintaining the designed working pressure under load — before considering the cylinder as a suspect. A cylinder that is physically intact, correctly specified, and properly installed will not be the limiting factor in a system where pressure and flow are adequate.
Measuring for Replacement: TF1204 / TF1304 Configuration
Measure all four primary dimensions. At 100 mm bore, this cylinder is uniquely identified within the 535 mm / 200 mm stroke subgroup. Also note the exact reference number from the existing cylinder for the end-connection confirmation step.
| Measurement | Target Value | Method |
|---|---|---|
| Mounting Distance | 535 mm | Pin-center to pin-center, fully retracted |
| Stroke | 200 mm | Extended pin-pin (735 mm) minus retracted (535 mm) |
| Bore ← unique identifier | 100 mm | Inside barrel diameter; confirms TF1204/TF1304 within the 535 mm / 200 mm subgroup |
| Rod Diameter | 40 mm | Calipers on clean rod surface; larger than other cylinders in this stroke subgroup |
| Rod-end pin diameter | To be measured | Calipers; will be larger than on 32 mm or 35 mm rod cylinders |
| Base-end pin diameter | To be measured | Measure separately; may differ from rod end |
| End connection type | To be confirmed | Clevis, eye, or other; may differ between TF1204.551.1 and TF1304.55.012 variants |
| Reference number on body | TF1204.551.1 or TF1304.55.012 | Check for stamped or labeled marking on cylinder body or end caps |
| Port specification | To be confirmed | Thread type and size, number of ports, port location |
On measuring bore for large-diameter cylinders: At 100 mm bore, the barrel outside diameter will typically be in the range of 115–130 mm depending on wall thickness and construction method. If the cylinder cannot be disassembled for direct bore measurement, estimate from the outer barrel diameter. For an inquiry based on estimated bore rather than direct measurement, note this clearly — a confirmed bore measurement from a disassembled cylinder or from machine documentation is more reliable than an estimate from the barrel OD.
Diagnosing Lift Faults on a 100 mm Bore Cylinder System
At 100 mm bore, the hydraulic system is handling substantial force levels. Two considerations specific to large-bore cylinders are worth keeping in mind when diagnosing faults.
Load drift under sustained hold
A 100 mm bore piston has approximately 7,854 mm² of area. Even a small leak past a worn piston seal — say, 0.1 cm³/s — will cause visible drift because the bore area is large. Isolate the cylinder by capping its ports before attributing drift to the piston seal. If drift stops with ports capped, the leakage is in the control valve or check valve circuit. Continue monitoring the drift rate with load: load-dependent drift (heavy load drifts faster) is more characteristic of internal piston bypass; load-independent drift points toward control valve leakage.
Slow lift speed despite adequate pressure
A full extension cycle on a 100 mm bore, 200 mm stroke cylinder displaces approximately 1,571 cm³ of fluid. If pressure at the cylinder port is adequate but lift speed is slow, the constraint is flow — not pressure. A pump delivering insufficient flow will produce slow extension regardless of whether the pressure relief setting is correct. Check pump output rate, not just system pressure, when diagnosing slow lift on a large-bore cylinder.
Rod seal failure pattern
A 40 mm rod seal on a 200 mm stroke cylinder traverses substantial rod surface area per cycle. If rod seal failure is recurring — multiple replacements in a short period — examine the rod surface carefully under good lighting and consider whether the wiper seal is also worn. A hardened or cracked wiper allows abrasive contamination to reach the rod seal on every retraction, progressively scoring the rod surface and destroying each new seal in turn.
Port fitting leakage
Port fittings under high pressure and vibration can develop leaks at the thread or at the fitting seat over time. On a 100 mm bore cylinder at high system pressure, even a small port leak can drip visibly during operation. Check port fittings with the system at operating pressure — a fitting that seals at low pressure may weep at full working pressure. Retorquing port fittings to the correct specification often resolves minor port leaks without seal or fitting replacement.
Requesting a Quotation for TF1204 / TF1304
Include the exact reference number alongside all four primary dimensions. Since two model numbers share the same core specification, the reference number helps identify any variant-specific end-connection or port detail that dimensional measurement alone may not capture.
- Reference number: TF1204.551.1 or TF1304.55.012 — specify which applies
- Confirmed bore: 100 mm
- Confirmed rod diameter: 40 mm
- Confirmed stroke: 200 mm
- Confirmed mounting distance: 535 mm
- Pin diameters at rod end and base end (both ends; measure separately)
- End connection type at both ends
- Any body markings, casting codes, or stamped identifiers visible on the cylinder
- Port thread type, size, count, and location
- Single-acting or double-acting (from port count)
- Order quantity
- Machine model and year, if known
- Working pressure, if known from machine documentation
- Photos of existing cylinder: full side view, both ends, port detail, any markings or damage
Frequently Asked Questions — TF1204 / TF1304
What is the difference between TF1204.551.1 and TF1304.55.012?
Both share the same core specification: 100 mm bore, 40 mm rod, 200 mm stroke, 535 mm mounting distance. The different prefix codes (TF1204 vs TF1304) most likely indicate different application designations — possibly from different machine models’ parts catalogues within the same manufacturer family, or a design revision that changed the reference number while keeping the geometry identical. Whether they differ in end-connection detail, port specification, or are truly identical in all dimensions is best confirmed by noting the reference number on your existing cylinder and including it in the inquiry alongside all measured dimensions.
Can I use TF1204.551.1 in place of TF1304.55.012 or vice versa?
Based on the available specification, the four primary dimensions are identical. If the end-connection geometry and port specification also match — which requires physical verification of the existing unit — then either reference number would produce a physically compatible replacement. However, without confirmed documentation showing the two are fully identical in all details, the safest approach is to specify the reference number that matches your existing cylinder rather than assuming the two are fully interchangeable without verification.
How does the 100 mm bore compare to the 90 mm TF1004 in force output?
Approximately 23–24% more force at the same pressure. The 100 mm bore piston area is about 7,854 mm² versus 6,362 mm² for the 90 mm bore — a difference of approximately 1,492 mm². At 160 bar reference pressure, this translates to approximately 125.7 kN for the 100 mm bore versus 101.8 kN for the 90 mm bore. These are theoretical reference figures; actual output depends on operating pressure and circuit conditions.
Why is the rod diameter 40 mm on a 100 mm bore cylinder — is that proportionate?
The rod-to-bore ratio is 40/100 = 0.40, which is consistent with the FT800.55A.012’s ratio (32/80 = 0.40) and within the narrow 0.39–0.41 band seen across the 80–110 mm bore cylinders in the 535 mm group. For a 200 mm stroke cylinder at the force levels this bore generates, a 40 mm rod provides adequate buckling resistance and side-load tolerance in a well-aligned installation. The heavier rod also means proportionally more robust end-connection hardware — pin diameters and clevis dimensions sized for 40 mm are meaningfully heavier than those for 32 mm or 35 mm rods, appropriate for the higher loads this cylinder transmits.
My tractor is not lifting to rated capacity — could this cylinder be the cause?
Possibly, but less likely than a system pressure issue. A cylinder with internal bypass will typically show as load drift — the implement slowly lowering when controls are held in neutral — rather than as an inability to reach lifting capacity in the first place. If the machine cannot lift its rated load to full height, check hydraulic system pressure under load first. A pump that has lost efficiency, a relief valve set too low, or a significant flow restriction in the circuit will all reduce effective lift capacity before a worn piston seal would. If system pressure confirms correct, then internal bypass investigation is the next step — using the port-capping isolation test.
What information should I provide for an accurate quotation?
The reference number (TF1204.551.1 or TF1304.55.012 — whichever appears on the existing cylinder), confirmed bore (100 mm), rod diameter (40 mm), stroke (200 mm), and mounting distance (535 mm). Add pin diameters at both ends, end connection type, port thread specification and count, and quantity. Any body markings or stamped codes on the existing cylinder are useful for confirming variant details. Machine model and year, working pressure if known, and photos of both mounting ends and side view complete the inquiry package. For this dual-reference model, including the exact reference number alongside the measured dimensions gives the most reliable basis for confirming the correct replacement.
