Compare the 4 TB and 8 TB exact drives without treating nominal capacity as usable mirrored storage.
The decision in brief
How the options differ
These are two distinct Red Plus parts, not one drive with a capacity label changed. The useful choice starts with the storage layout and growth plan; it is not a promise that the larger disk doubles every performance measure.
By CompareFoundry · Published · Editorial review · Manufacturer documentation, not hands-on testing.
The buying guide
Package and specification details
Plan the array before choosing capacity
WD40EFPX is the 4 TB selection and WD80EFPX is the 8 TB selection. In a two-drive mirror, equal drives provide one drive of nominal capacity before formatting and system overhead. Check the NAS rules before mixing capacities or replacing members of an existing array.
The exact tables list 5400 rpm for WD40EFPX and 5640 rpm for WD80EFPX, with maximum transfer figures of 180 MB/s and 215 MB/s respectively. Both list 256 MB of cache. These source-specific maxima are not application benchmarks or a noise comparison.
Both selections have a stated 180 TB/year workload rating and a 3-year limited warranty. That does not certify either drive for your exact NAS and firmware. Confirm the delivered label and warranty eligibility, and keep a separate recoverable backup.
These manufacturer specifications do not establish measured performance, noise, long-term reliability or running cost. We have not independently tested these products. Check current prices, stock and operating-space instructions with the seller and manufacturer.
Select the exact part number and capacity. A different suffix, condition or seller can change the hardware and warranty scope.
No enclosure, drive-pair compatibility result, current price or available-stock claim is included. Confirm any cables or mounting accessories with the seller.
Select the exact part number and capacity. A different suffix, condition or seller can change the hardware and warranty scope.
No enclosure, drive-pair compatibility result, current price or available-stock claim is included. Confirm any cables or mounting accessories with the seller.
The link may open several packages. Check current price and availability with the seller. Opens in a new tab.
Nominal capacity
Manufacturer capacity of the exact drive model.
Formatting, storage layout and system overhead reduce usable capacity; a mirror does not add both drive capacities.
Red Plus WD40EFPX (4 TB) (US single drive)4 TBSource · 2026-10-13Western Digital: WD40EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Red Plus WD80EFPX (8 TB) (US single drive)8 TBSource · 2026-10-13Western Digital: WD80EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Physical format and interface
Documented drive size and connection family.
Check the NAS bay and interface. SATA hardware alone does not establish an approved drive and firmware pairing.
Red Plus WD40EFPX (4 TB) (US single drive)3.5-inch SATASource · 2026-10-13Western Digital: WD40EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Red Plus WD80EFPX (8 TB) (US single drive)3.5-inch SATASource · 2026-10-13Western Digital: WD80EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Recording method
The recording method explicitly stated for this part number.
CMR is a recording technology, not a measured reliability score or a NAS compatibility certificate.
Red Plus WD40EFPX (4 TB) (US single drive)CMRSource · 2026-10-13Western Digital: WD40EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Red Plus WD80EFPX (8 TB) (US single drive)CMRSource · 2026-10-13Western Digital: WD80EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Spindle speed
Manufacturer-reported rotational speed for the exact capacity and model.
Do not transfer a speed from another capacity in the same family or use RPM alone to predict noise or application performance.
Red Plus WD40EFPX (4 TB) (US single drive)5400 rpmSource · 2026-10-13Western Digital: WD40EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Red Plus WD80EFPX (8 TB) (US single drive)5640 rpmSource · 2026-10-13Western Digital: WD80EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Drive cache
Cache capacity listed for the exact model.
Cache size does not measure sustained file-transfer speed; similarly named drives may use different cache capacities.
Red Plus WD40EFPX (4 TB) (US single drive)256 MBSource · 2026-10-13Western Digital: WD40EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Red Plus WD80EFPX (8 TB) (US single drive)256 MBSource · 2026-10-13Western Digital: WD80EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Rated annual workload
The manufacturer annual workload rating, not a lifetime write allowance.
Keep the source definition and operating conditions. A higher rating does not guarantee a longer life or replace a backup.
Red Plus WD40EFPX (4 TB) (US single drive)180 TB/yearSource · 2026-10-13Western Digital: WD40EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Red Plus WD80EFPX (8 TB) (US single drive)180 TB/yearSource · 2026-10-13Western Digital: WD80EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Limited warranty term
Published manufacturer limited-warranty duration for the reviewed new-drive scope.
Check seller, condition, region and serial-number eligibility; used, refurbished and OEM offers can have different coverage.
Red Plus WD40EFPX (4 TB) (US single drive)3 yearsLimited manufacturer warranty; verify the eligibility of the delivered new-drive serial number and seller.Source · 2026-10-13Western Digital: WD40EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Red Plus WD80EFPX (8 TB) (US single drive)3 yearsLimited manufacturer warranty; verify the eligibility of the delivered new-drive serial number and seller.Source · 2026-10-13Western Digital: WD80EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Published maximum transfer rate
A source-specific maximum sequential or sustained transfer figure.
Manufacturer methods differ. This is not a CompareFoundry benchmark, network rate or guaranteed speed throughout the disk.
Red Plus WD40EFPX (4 TB) (US single drive)180 MB/sManufacturer maximum for this exact part; not a measured NAS or network result.Source · 2026-10-13Western Digital: WD40EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Red Plus WD80EFPX (8 TB) (US single drive)215 MB/sManufacturer maximum for this exact part; not a measured NAS or network result.Source · 2026-10-13Western Digital: WD80EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Drive weight
The published weight of the drive, not its shipping package.
Use the NAS installation instructions; a weight figure does not describe operating clearance, vibration or supplied mounting hardware.
Red Plus WD40EFPX (4 TB) (US single drive)570 gSource · 2026-10-13Western Digital: WD40EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Red Plus WD80EFPX (8 TB) (US single drive)715 gSource · 2026-10-13Western Digital: WD80EFPX exact-model specificationsChecked 2026-10-13. We reviewed the official page text on the check date. Checkout options were not verified.
Verified NAS and firmware pairing
An exact enclosure, drive and firmware compatibility result, when separately established.
An unknown entry means this catalogue has not established the pairing. It does not mean that the drive is incompatible.
Red Plus WD40EFPX (4 TB) (US single drive)Not verified
We have not verified this value. It is not a confirmed no or zero. Check the original source or ask the manufacturer if it affects your choice.
No exact NAS model, operating-system version and drive-firmware pairing was established in this category review.
Red Plus WD80EFPX (8 TB) (US single drive)Not verified
We have not verified this value. It is not a confirmed no or zero. Check the original source or ask the manufacturer if it affects your choice.
No exact NAS model, operating-system version and drive-firmware pairing was established in this category review.
Questions to check before buying
Red Plus WD40EFPX (4 TB) (US single drive)Read the source notes for the exact package and operating conditions.
Red Plus WD80EFPX (8 TB) (US single drive)Read the source notes for the exact package and operating conditions.
Allow Google Analytics to measure page visits, engagement and clicks to sellers? It uses analytics cookies. Your choice won’t affect the comparison tools. Read our privacy policy.