When an engine overhaul is scheduled, a purchasing team can reduce back-and-forth by recording the engine serial number and the exact seal location before asking for a quote. The Cummins QSM11 crankshaft oil seal 3804304 is a useful catalog starting point, but the listing alone is not a fitment decision for every QSM11 engine.
A Cummins crankshaft seal replacement request should specify front or rear as confirmed by the workshop. If the mechanic has only described the side of the machine where oil was found, ask for the position on the engine itself. A photo of the installation area and a marked engine diagram are more useful than a note saying “the seal on the left.” Do not assign either position to 3804304 just because a search result uses the words “front” or “rear.”
Record the engine serial number from the installed engine plate. Use the equipment serial number as supporting information, not as a substitute for it. On a machine that has had an engine change, the original equipment parts list may describe a different engine build. If the buyer has a number from an old invoice, label it as a previous purchase reference until someone matches it to the current engine and position.
“Oil leaking near the crankshaft” describes what the workshop sees; it does not tell the supplier which seal to supply. Have the technician identify the leak location and confirm which end of the engine the request concerns. On the RFQ, put the required position next to the part number. If a catalog lookup gives a different number from the removed component, ask for the basis of the cross-reference before accepting it.
Photograph the engine plate square on, with enough light to read the stamped characters. Photograph the removed seal separately, including the face with its markings if those markings are still legible. If the workshop has a parts drawing, include the callout and the page that identifies the engine arrangement. A close-up with no drawing title or assembly context can leave the supplier guessing which version the callout belongs to.
If the seal is distorted during removal, avoid treating its measured size as the nominal specification. Report the measurement as an observation and say how it was taken. Where the service team has found wear or damage at the sealing surface, flag it in the repair notes. Ask separately whether a sleeve or another component is needed under the applicable service procedure; do not add a sleeve to the order on the assumption that all 3804304 listings include one.
A Cummins oil seal RFQ may produce more than one quote, especially if a supplier proposes a superseded number or an alternative brand. Ask the supplier to state which number will appear on the label, which engine and seal position the quote covers, and whether the offer is for a single seal or a kit. If an alternative is proposed, record it on a separate line until the person responsible for fitment approves the change.
For example, an inquiry can read: “Reference 3804304 requested. Installed engine plate attached. Seal position to be confirmed by workshop. Please state the quoted part number and whether this offer includes any additional components.” That is a request for identification and price, not permission to ship an assumed substitute.
Compare the package label with the approved purchase order, including any suffixes or replacement numbers the supplier confirmed. If the label differs, hold the item for clarification before issuing it to the workshop. Keep the supplier’s written match confirmation with the order. A clear receiving record is especially useful when several seals for different engine builds arrive in the same shipment.
For seal 3804304, attach the engine nameplate or write out the engine serial number. Include a readable photo of the removed seal markings where available. If the supplier proposes a different reference, request a written confirmation that identifies the engine and seal position. Also ask whether the quote is for a single seal or includes any additional components; do not infer kit contents from a photo.
If the overhaul calls for seals at both ends of the engine, give each position its own line item. Do not copy 3804304 onto the second line unless the supplier confirms that reference for that position. The same rule applies to a multi-engine order: keep each seal tied to the engine serial number used to identify it.
Can I order 3804304 from “QSM11” alone? Use QSM11 to start the search, then confirm the engine serial number, seal position, and part reference before ordering. If any of those details are unknown, mark them as pending on the RFQ.
The diesel cooling parts guide shows how to record engine identity before quoting. Use the seal kit order scope guide when the workshop also needs a separately specified kit or accessory.
