The Case IH Farmall 40A tractor primary air filter part number is 84386403. The inner safety filter is 381423R92.
Case IH Farmall 40A Air Filter Details
| Primary air filter part number | 84386403 |
|---|---|
| Inner safety air filter part number | 381423R92 |
| Outer air filter part number | 381423R92 |
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 40A Extra Air Filter Notes
| Engine horsepower | 40 hp | 29.8 kW |
|---|---|
| Primary filter note | For the Case IH Farmall 40A, the listed primary air filter part number is 84386403. Match the number before buying because air cleaner setups can vary by engine, serial range and market. |
| Outer filter note | The listed outer air filter part number is 381423R92. |
| Safety filter note | The listed inner safety air filter is 381423R92. 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 40A Air Filter FAQs
What is the safest way to match a Case IH Farmall 40A air filter?
Do not buy from the title alone. Match 84386403 against the removed filter, then check gasket shape, end-cap depth and cover fit before starting the tractor.
What should I buy for a full Case IH Farmall 40A air-filter service?
For a full parts check, separate the service element from the safety element: buy the outer/primary service element first, then buy the inner safety element only if it is dirty, damaged or due. Do not accidentally order 381423R92 when you meant the safety filter, or 381423R92 when you meant the outer filter.
What order should I check the Case IH Farmall 40A air-filter elements?
The outer filter is the dirt-catcher; the inner filter is the backup. Service them with different expectations instead of replacing both out of habit.
What symptoms point to air restriction on a Case IH Farmall 40A?
This sits in the utility range. The 300-hour guide is useful for planning, but dusty work should shorten the inspection cycle.
What part-number mistake should I avoid on a Case IH Farmall 40A?
When there are several part numbers, do not search them all in one cart and hope. Label each one as primary, outer or safety before buying.
Why not buy a Case IH Farmall 40A air filter from model name alone?
The compact utility horsepower class changes how hard the filter works, but it does not prove the part number. Use horsepower for service urgency, not fitment.
Can I clean the Case IH Farmall 40A inner safety filter?
Because the setup includes a safety element, service the primary element first and inspect the inside of the housing. If dust reached the safety element, the job is no longer just a quick outer-filter swap.
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.
