The Case IH Farmall 40B tractor primary air filter part number is 381423R92. The inner safety filter is 187472A1.
Case IH Farmall 40B Air Filter Details
| Primary air filter part number | 381423R92 |
|---|---|
| Inner safety air filter part number | 187472A1 |
| Outer air filter part number | Same as primary air filter |
Air Filter Service Interval Guide
Air Filter Service Interval Guide
These are practical inspection/replacement guide ranges for the utility tractor category. Dusty work can shorten the interval heavily, so use the restriction indicator and operator manual first.
Case IH Farmall 40B Extra Air Filter Notes
| Engine model | Mitsubishi S4QL |
|---|---|
| Engine horsepower | 40 hp | 29.8 kW |
| Primary filter note | For the Case IH Farmall 40B, the listed primary air filter part number is 381423R92. Match the number before buying because air cleaner setups can vary by engine, serial range and market. |
| Outer filter note | The outer air filter for the Case IH Farmall 40B appears to be the same listed item as the primary filter. |
| Safety filter note | The listed inner safety air filter is 187472A1. Do not remove the safety element for normal cleaning; replace it if dirty, damaged or oil-soaked. |
| Fitment note | Check the old filter, air cleaner housing label and parts book before ordering if the tractor has had an engine or intake-housing change. |
| Power range note | This sits in the utility range. The 300-hour guide is useful for planning, but dusty work should shorten the inspection cycle. |
| Service note | Clean loose dust from the air cleaner housing before pulling the filter. Never run the tractor with the filter removed, even for a quick test. |
Case IH Farmall 40B Air Filter FAQs
How do I avoid buying the wrong Case IH Farmall 40B air filter?
The buying order should be: old filter number first, housing fit second, then cross-reference. Start with 381423R92, but do not ignore the a primary/outer service element plus an inner safety element.
Which Case IH Farmall 40B air-filter parts should be changed together?
For normal service, the primary/outer element is the one that does the dirty work. The inner safety element is backup protection, so replace it less often and keep it seated while cleaning the housing.
Why does airflow matter on the Case IH Farmall 40B air filter?
This sits in the utility range. The 300-hour guide is useful for planning, but dusty work should shorten the inspection cycle.
How can part-number style help check a Case IH Farmall 40B filter?
Use the full 381423R92 string. Do not trim suffixes or ignore letters; small part-number changes can mean a different seal or element length.
What order should I check the Case IH Farmall 40B air-filter elements?
Primary versus outer is wording more than a separate part in this data. The safety element is the one that needs separate treatment.
Can a Case IH Farmall 40B engine swap change the air filter?
The engine clue is helpful, but the filter still has to seal in the actual housing. Fit beats theory here.
Should I blow out the Case IH Farmall 40B inner safety element?
On a a primary/outer service element plus an inner safety element, the inner element is the last barrier. If you remove it casually in a dusty shed, you defeat the reason it exists.
Mistakes do happen. Air filter specs can change by year, engine, serial range, market and air cleaner housing. Check the old filter, operator manual, parts book and official caseih.com website before ordering or installing an air filter.
