The contact owns a 2008 Toyota Sienna. The contact stated while pulling into a grocery store, he heard an abnormal ticking sound. The contact stated upon parking and inspecting the outside of the vehicle, he noticed that engine oil was leaking onto the ground. Additionally, the oil dipstick was dry upon inspecting the oil level. There was no warning light illuminated. The vehicle was taken to a…
2008 Toyota Sienna engine problems
moderate 42 complaints filed with NHTSA · avg repair $3,100 · see engine across all vehicles →
Failure mileage
Complaints
42
Recalls
0
Avg fix
$3,100
2fires
When does it fail?
Of the 42 engine complaints filed for the 2008 Toyota Sienna, here's the actual mileage breakdown — failures cluster heaviest at 150,000+ mi.
0-25k
25-50k
50-75k
75-100k
100-125k
125-150k
150k+
Each bar shows the share of total complaints filed at that mileage range. Peak failure window highlighted. Some owners report problems earlier; some make it well past 150,000 miles symptom-free. Maintenance habits and driving conditions shift the curve as much as mileage alone.
What stands out
Owners have filed 42 engine complaints with NHTSA against this vehicle, but no formal recall covers the issue — the federal record reflects what manufacturers have admitted, not everything owners are reporting.
Among the 12 model years of Toyota Sienna in our records for engine problems, this one ranks #2 by owner-complaint volume.
The failure pattern owners describe
Buyer takeaway: The 2008 Sienna has a known, serious defect in its engine oil supply lines (particularly the VVT rubber hose) that fails without warning, causing rapid oil loss, engine damage, potential fires, and even total vehicle loss at highway speeds. Even after warranty service or recalls, the same component may fail again with the faulty rubber design.
The dominant failure pattern is catastrophic oil line rupture. Owners report the variable valve timing (VVT) oil supply line or oil cooler hose bursts suddenly—at 50,000 to 80,000 miles, sometimes earlier—draining all oil within minutes. No check engine light, no oil pressure warning, no advance notice. One owner lost all pressure at highway speed on an interstate; another's van caught fire and was totally consumed. A third had complete brake and power steering failure occur simultaneously, trapping the family inside.
The rubber portion of these hoses degrades under pressure and either develops pinhole leaks that spray fine mist across other vehicles, or ruptures completely, leaving visible oil trails for miles. Hot oil hitting the catalytic converter or engine block ignites. Several owners experienced smoke, burning smells, and immediate fire risk.
Toyota issued a voluntary recall (not a formal recall) with a 2013 deadline, but many owners were never notified. The same hose component was recalled in other Toyota models like the Camry and Avalon. When dealers replace the line during the recall window or voluntarily, some have installed the same faulty rubber-hose design again instead of the newer metal version.
Other failures include camshaft fracture, head gasket failure, and engine stalling with no diagnostic codes. Piston slap noise is deemed normal by Toyota despite owner concerns about premature wear. Engine replacements cost $10,000; oil line repairs run $429–$520 at dealer, but many are denied warranty coverage since Toyota classifies the hose itself as outside the powertrain warranty.
Same Toyota Sienna engine reports on nearby years: 2005 · 2007 · 2011
Failure modes owners describe
VVT Oil Line (Variable Valve Timing Oil Supply Line) Rupture
The rubber oil supply hose for the variable valve timing (VVT/VVT-I) actuator fails suddenly, causing rapid oil loss. Owners report the hose ruptures, perforates, or bursts without warning, emptying the oil pan in minutes to seconds. The rubber portion of the hose degrades or fails under pressure.
When: Typically 50,000–80,000 miles, though failures reported across mileage range
Symptoms owners cite: Sudden large oil loss visible as puddles or trails on ground and road; No warning lights or check engine light before failure in many cases; Burning smell or white/blue smoke from engine or under hood; Rattling or tapping noise from engine; Oil dipstick reading dry or nearly dry when checked; Brake power loss and power steering loss in extreme cases
Repairs/costs cited: Replacement hose/line cost $429–$520 at dealerships. Newer factory parts use metal instead of rubber. Owners report replacement hose sometimes supplied with same faulty rubber component.
Recalls/TSBs owners mention: Toyota issued a Technical Service Bulletin (TSB) and a voluntary 'internal recall' around 2010 with a 3/31/13 deadline; not a formal recall. Toyota recalled the same component in other models (Camry, Avalon) but not the 2008 Sienna. Some owners report Toyota offered extended warranty but did not notify owners or recalled within warranty window.
Oil Cooler Hose/Line Rupture (Flexible Material with Pin-Hole)
A separate oil cooler hose fails with a pin-hole puncture or rupture in the flexible rubber material, forcing all engine oil out under high pressure. Distinct from the VVT oil line; dealerships note it has not been recalled but factory replacement is now metal instead of original rubber.
When: Mileage varies; one case at 74,000 miles
Symptoms owners cite: Sudden complete oil loss (quarts empty in minutes); Pool of oil under engine; Burning smell; No warning lights or engine noise before catastrophic failure in some cases; Oil trail visible on road behind vehicle; Smoke from engine compartment
Repairs/costs cited: Replacement with metal line costs approximately $429–$442. Engine replacement may be required if oil loss causes full engine damage; owners cite $10,000 engine replacement costs.
Recalls/TSBs owners mention: Dealerships state no recall on this component, though acknowledge it as a design issue and confirm factory has switched to metal. Warranty does not cover the failed hose/line itself, leaving engine damage liability on owner.
Engine Oil Leak—Multiple Lines, Loss of All Oil and Engine Fire
Combination of oil line failures and leaks resulting in complete oil loss and fire risk. Oil sprays onto hot catalytic converter and engine components, igniting. Multiple rapid cascading failures (AC quit, brakes failed, power steering failed) reported alongside oil leak.
When: No specific mileage given for one critical fire case
Symptoms owners cite: AC system suddenly stops working; White smoke from under vehicle and engine compartment; Brake power loss; Power steering loss; Oil dripping from bumper and tailpipe; Flames visible at engine within seconds; Engine spontaneously engulfed in fire; No warning lights or sounds before failure
Repairs/costs cited: Vehicle totally destroyed by fire; no repair possible. Oil trail visible for multiple miles behind vehicle.
Recalls/TSBs owners mention: No recall notification received by owner prior to fire event.
Camshaft Fracture or Faulty Camshaft
Exhaust camshaft cracks or fractures, causing internal engine damage. One case shows repeated failure: engine rebuilt in 2011, camshaft repaired in 2016, and faulty camshaft diagnosed again at 170,000 miles.
When: High mileage (170,000 miles for repeated failure case); one case at 204,000 miles with exhaust cam gear fracture
Symptoms owners cite: Engine hesitation and shuddering before stalling; Engine stalling while driving; Loud abnormal engine noise (ticking, knocking)
Repairs/costs cited: Engine rebuild or full replacement required. Costs not stated for camshaft repair alone, but owners face significant repair burden.
Recalls/TSBs owners mention: Manufacturer declined assistance citing vehicle age/mileage outside warranty.
Engine Stalling with No Diagnostic Codes
Engine stalls multiple times with full instrument panel illumination, but no trouble codes detected by dealers. Vehicle stalls at highway speed (65 mph) and again at lower speeds (25 mph), with steering becoming very difficult to control.
When: Approximately 34,680 miles for one case; 80,000 miles for another
Symptoms owners cite: Complete engine stall while driving; Entire instrument panel lights up/flickers; No restart; vehicle must be towed; Steering becomes extremely difficult to control; Repeated stalls on same day or within short period; Engine stalls at both highway and low speeds
Codes mentioned: No trouble codes detected by two separate dealers
Repairs/costs cited: Unable to determine from complaints; dealers could not locate problem.
Recalls/TSBs owners mention: Manufacturer notified but no assistance offered or problem identified.
Piston Slap Noise (3.5L V6)
Loud piston slap noise, especially when cold or in cooler temperatures. Owner reports this is normal per Toyota arbitrator, but believes it indicates premature piston wear that could lead to engine failure.
When: Since new; present in cold temperature operation
Symptoms owners cite: Very loud noise from engine when cold; Noise present in cooler temperatures
Repairs/costs cited: No repair performed; Toyota and arbitrator classify as normal.
Recalls/TSBs owners mention: Toyota acknowledges complaints but declares piston slap normal for this engine; no warranty repair offered.
Head Gasket Failure and Radiator System Failure
Head gasket repaired by dealer fails again; radiator system also fails. Unclear whether failures are dealer-related (installation/service) or manufacturing defect.
When: After prior repair by dealer
Symptoms owners cite: Head gasket leak or failure; Radiator system failure
Repairs/costs cited: Not stated; owner questioning whether issue is dealer service quality or manufacturing.
Recalls/TSBs owners mention: None stated.
Engine Water Hose Malfunction
Engine water hose malfunctions alongside oil hose issue, causing ruined engine after check engine light illuminates.
When: After two hours of driving
Symptoms owners cite: Air conditioning not cooling vehicle (thought to need service only); Check engine light illuminates; Engine ruined by the time vehicle can pull over
Repairs/costs cited: Engine ruined; full replacement needed.
Recalls/TSBs owners mention: None stated.
Push Rod Fracture with Engine Hole
Push rod fractures, creating a hole in the engine block.
When: 60,600 miles
Symptoms owners cite: Smoke rolling from engine
Repairs/costs cited: Engine replacement required.
Recalls/TSBs owners mention: Manufacturer aware of failure but no assistance offered; no repair performed by customer.
Timing Chain Gasket Leak
Toyota-known defective timing chain gasket leaks oil.
When: Not specified
Symptoms owners cite: Oil leak
Repairs/costs cited: Not specified.
Unintended Engine Speed Increase (Possible Throttle Control Issue)
Engine speed climbed slowly without driver foot on gas pedal, simulating unintended acceleration. Floor mat ruled out as cause.
When: 20,000 miles
Symptoms owners cite: Engine speed climbs without driver depressing gas pedal; Single occurrence
Repairs/costs cited: No repair documented.
Recalls/TSBs owners mention: Owner reported to dealer and Toyota website.
Synthesized from 42 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 1 most recent
Had engine trouble with your 2008 Toyota Sienna?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2008 Toyota Sienna?
It's a documented issue but not catastrophic. 42 complaints have been filed. Repairs average $3,100 and most owners catch it before it causes a breakdown.
At what mileage does the engine typically fail?
Across the 38 complaints that reported odometer mileage, most engine failures cluster between 51,303 and 98,000 miles, with the median around 80,000. A quarter of owners report trouble before 51,303; a quarter make it past 98,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2008/Toyota/Sienna.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.