Is oil cap profitable to sell on Amazon United States?

The niche generates $97K/yr across 96 tracked products. 1 of 15 products launched in the last 360 days are still selling. 90-day search growth is -15.6%. Flapen's verdict: Worth a look (53/100).

How competitive is the oil cap niche?

37 brands and 132 sellers compete. The top 5 products take 22% of clicks and top 5 brands hold 56% of demand.

What do buyers complain about in oil cap?

Top complaints mined from reviews: Size-Overall, Compatibility-Overall, Durability. The return rate is 3.6%.

When does demand for oil cap peak?

Demand is steady year-round — the busiest month runs 1.3× the quietest.

What does it cost to enter the oil cap niche?

Listings span $5.50–$20.70; the average listing price is $10.35 (sweet spot $15–$100). The average incumbent carries 187 reviews — the moat a new listing must climb.

oil cap

Worth a look

Shows a fragmented shelf (top 5 take 22% of clicks), but soft demand (-15.6% this quarter) keeps it on the watch list.

Competition

Great22%

top-5 click share — an open shelf

Review moat

Great186.53

avg incumbent reviews — the moat a new listing must climb

Brand share

Great56%

top-5 brand share — no brand owns this niche

Quality gap

Great4.3★

avg incumbent rating — lower means beatable quality

Conversion

Good4.3%

search→purchase rate — share of searches ending in a sale

Returns

Okay3.6%

return rate — above 5% kills the launch gate

Price range

Okay$5.50–$20.70

cheapest to priciest tracked listing — scored on the share inside $15–$100

Avg price

Okay$10.35

avg listing price — sweet spot $15–$100

Market size

Bad$97K

$97K/yr · 218K searches

Growth

Bad-15.6%

90-day search growth — must beat 0% to launch

According to Flapen's Amazon United States niche tracking, oil cap is a $97K/yr Amazon United States market (218K searches/yr). The top 5 brands hold 56% of demand. Verdict: Worth a look — 53/100.

Data updated Jul 9, 2026 · scored weekly · How we score niches

oil cap market data

Units sold / yr: 10K–13K; avg 0–100/product
Revenue / yr: $104K–$129K; units × avg price
Conversion rate: 4.3%
Avg BSR: #1,601
Page quality: 0%
Prime: 100%
Sponsored: 61%
Out of stock: 0.6%
Avg brand age: 50 months
Avg seller age: 168 days

Competition & brand share

Clicks spread well past the top 5 (22% combined) — an open shelf where new products get seen.

Brands

37 falling

Sellers

132

Top-5 brand share

56%

Top 20: 89%

Top-5 click share

22%

Top 20: 48%

Open market

39%

Manymiba24%
ACDelco12%
KUQUTIDY9%
MotoRad7%
A-Premium5%
Anleecap5%

Demand & seasonality

Weekly Amazon search volume, last 104 weeks — -15.6% search growth over the last 90 days.

No pronounced peak months · busiest ÷ quietest = 1.3×

Open Trend

Top oil cap search terms

oil cap94K/yr -15.6%3.6% conv.
oil filler cap33K/yr -6.3%3.7% conv.
oil cap replacement32K/yr -7.8%4.2% conv.
engine oil cap15K/yr -19.3%4.0% conv.
oil fill cap11K/yr -14.1%3.6% conv.
tapa de aceite de motor6K/yr -16.5%1.5% conv.
oil cap gasket5K/yr -18.8%2.3% conv.
engine oil filler cap5K/yr -13.6%2.8% conv.
automotive replacement oil filler caps5K/yr -22.9%2.5% conv.
engine oil cap replacement4K/yr -24.9%3.6% conv.

All search terms

Top oil cap products on Amazon

Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.

Beatable (≤4.3★) Contested Strong incumbent (>4.7★)1 product missing review or click data not plotted

All 24 tracked products in this niche — three views at once, no toggling.

Top sellers

by 90-day click share

KUQUTIDY Engine Oil Filler Cap Replacement Compatible with GM 1992-2018 1994-2011 Chevrolet GMC Cadillac Buick Oldsmobile Pontiac Hummer Saab Isuzu Repalce FC208 12573337

KUQUTIDY$9.023.6★67 rev

Engine Oil Filler Cap for Dodge Ram Jeep Chrysler 1997-2003 Ram 1500 2500 3500 Wrangler Cherokee Caravan Dakota Durango Intrepid Neon Stratus Concorde PT Cruiser 53010654AA 04648831AA

Manymiba$7.454.6★70 rev

KoiLuvGo Engine Oil Filler Cap Replacement Compatible with GM 1992-2018 1994-2011 Chevrolet GMC Cadillac Buick Oldsmobile Pontiac Hummer Saab Isuzu Replaces OEM #FC208 12573337

KoiLuvGo$9.072.5★15 rev

ACDelco GM Original Equipment FC219 (12589430) Engine Oil Filler Cap

ACDelco$14.894.7★1,414 rev

ACDelco GM Original Equipment FC208 (12573337) Engine Oil Filler Cap

ACDelco$10.774.7★1,496 rev

Newest

by launch date

KoiLuvGo Engine Oil Filler Cap Replacement Compatible with GM 1992-2018 1994-2011 Chevrolet GMC Cadillac Buick Oldsmobile Pontiac Hummer Saab Isuzu Replaces OEM #FC208 12573337

KoiLuvGo$9.0715 rev

4mo ago

ESWW Engine Oil Filler Cap Replacement Durable Oil Fill Cap for Secure Sealing Leak-Proof Tight Fit Design with Identification Pattern Replaces OEM 06K103485A Compatible with VW Audi

ESWW$7.161 rev

6mo ago

WZP OD 2/50.8mm Oil Filler Cap Aluminum Alloy Weld Billet On Filler Neck Cap Oil Universal Replacement for Oil Fuel Water Tank (Black)

WZP$8.320 rev

6mo ago

KUQUTIDY Engine Oil Filler Cap Replacement Compatible with GM 1992-2018 1994-2011 Chevrolet GMC Cadillac Buick Oldsmobile Pontiac Hummer Saab Isuzu Repalce FC208 12573337

KUQUTIDY$9.0267 rev

9mo ago

Engine Oil Filler Cap for Dodge Ram Jeep Chrysler 1997-2003 Ram 1500 2500 3500 Wrangler Cherokee Caravan Dakota Durango Intrepid Neon Stratus Concorde PT Cruiser 53010654AA 04648831AA

Manymiba$7.4570 rev

1y ago

What buyers say about oil cap

What buyers praise and complain about, mined from review topics.

What buyers love

Size-Overall59%

“Fit my jeep”

Quality-Overall10%

“Good quality”

Advertised Vs Actual Product7%

“Works as advertised”

Value For Money6%

“Good Value”

Efficiency3%

“Works well”

Lubrication3%

“The oil cap was decent”

Leak-Proof1%

“Fixed my oil leak on 09 ford escape 3.0 v6”

Design-Overall1%

“Works as designed”

Assembly/Installation1%

“Installation was super easy”

Functionality-Overall1%

“Item works as described”

What buyers complain about

Size-Overall35%

“it doesnt fit my Car”

Compatibility-Overall20%

“Not compatible”

Durability8%

“fell off after a few of days of driving”

Quality-Overall7%

“The quality is the part that I am questioning as the part appears to be a little bit smaller on the top part”

Advertised Vs Actual Product5%

“Inaccurate information”

Leak-Proof3%

“it had started leaking a mess I didnt think I could find an alternative”

Defective Material/Parts2%

“Defective part”

Jamming/Clogging1%

“There is a manufacturers defect in the motor causing the PCV valve to clog”

Fastener Quality1%

“The cap actually screws in so it doesnt pop off like a cheap plug”

Weight Heavy1%

“A mere paperweight”

Top return reasons

Size-Overall70%

Compatibility-Overall14%

Advertised Vs Actual Product6%

Defective Material/Parts4%

Value For Money2%