Was driving and suddenly the exhaust got real loud. Took it to repair facility and they said that the exhaust manifold had cracked. Gm knows this is a bad part , and a safety part, but they only advanced the warranty 20,000 miles. I have never had an exhaust manifold crack on any vehicle, besides one that is 6 years old. *tr
2008 Chevrolet Trailblazer engine problems
moderate 28 complaints filed with NHTSA · avg repair $3,100 · see engine across all vehicles →
Failure mileage
Complaints
28
Recalls
0
Avg fix
$3,100
When does it fail?
Of the 28 engine complaints filed for the 2008 Chevrolet Trailblazer, here's the actual mileage breakdown — failures cluster heaviest at 25,000-50,000 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 28 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 8 model years of Chevrolet Trailblazer in our records for engine problems, this one ranks #3 by owner-complaint volume.
The failure pattern owners describe
Buyer takeaway: Budget for a cracked exhaust manifold by 75,000 miles—the problem recurs even after dealer repair, and dealers may not cover repeats. More critically, sudden catastrophic engine failure requiring replacement has occurred at 50,000-plus miles on multiple examples, with owners reporting it's not preventable and unrelated to maintenance.
The 2008 Trailblazer engine complaints cluster around two dominant issues: cracked exhaust manifolds and sudden catastrophic engine failure.
The exhaust manifold cracking is the most frequent complaint. Owners report loud exhaust noise appearing at 42,000 to 75,000 miles. The manifold cracks in cast iron, and some owners describe it splitting around the entire pipe. What stands out is that this happens repeatedly even after dealer replacement—one owner had the manifold replaced twice under warranty, then faced the same problem again. Dealers apparently stock replacement manifolds, which owners interpret as evidence of a known defect. The repair runs $600-$700. One owner's concern about exhaust fumes entering the cabin in winter suggests a potential safety angle. Mechanics and owners alike blame defective design and cheap materials. GM issued Special Coverage Bulletin #11150 for this issue but capped coverage at 120,000 miles, leaving some owners unprotected.
The second serious problem is sudden engine failure—rod bearing seizure or rod failure at highway speeds (50,000 to 94,000 miles). These failures are catastrophic: violent shaking, smoking, stalling without warning, and requiring full engine replacement. One owner points to an oiling deficiency in the LS2 engine used in Trailblazer SS models. Dealers confirm these aren't owner-caused and dealers report nothing could have prevented them—suggesting a manufacturing defect.
Lesser complaints include ignition switch failures causing stalling at low speeds, and various stalling events at 35–72,000 miles that dealers sometimes cannot reproduce.
Same Chevrolet Trailblazer engine reports on nearby years: 2005 · 2006 · 2007
Failure modes owners describe
Cracked Exhaust Manifold
Cast iron exhaust manifold develops cracks, typically becoming audible as loud exhaust noise. Owners report the manifold fails repeatedly even after dealer replacement. Multiple owners note seeing part stock at dealerships, suggesting high frequency of the problem. Cracks can allow exhaust fumes to enter the cabin in winter. Owners and mechanics cite defective design and cheap materials as root cause.
When: 42,000 to 75,000 miles, with some recurrence at higher mileage after replacement
Symptoms owners cite: Abnormally loud exhaust noise after startup; Visible cracks in exhaust manifold; Exhaust fumes entering cabin (winter months noted); Loud exhaust while driving
Repairs/costs cited: Replacement cost $600-$700. Dealer replacement available; dealers stock the replacement part indicating known issue. Multiple owners report dealer covered replacement under warranty initially but refused to cover second/third failure. Breaking bolts during DIY repair attempts reported.
Recalls/TSBs owners mention: Special Coverage GM Bulletin #11150 exists but limited to 120,000 miles, leaving some owners out of coverage. Dealers have replaced manifolds under warranty (first occurrence) but deny coverage for repeat failures. Some owners report GM working with them after direct contact.
Engine Rod Failure (Bearing Seizure)
Engine rod bearing seizes or spins, causing catastrophic engine damage. One owner reports LS2 engine in SS models has known oiling deficiency causing rod bearing failure; another reports rod burst through oil pan. Occurs suddenly while driving at highway speeds. Owners maintain regular maintenance and report mechanics indicate no owner fault or preventable cause.
When: 50,000 to 94,000 miles
Symptoms owners cite: Sudden violent shaking at highway speed (55 mph); Engine starts smoking; Sudden stall with no warning; Unable to restart after stall; Large amount of oil on ground; Rod burst through oil pan
Repairs/costs cited: Engine replacement required. Owners report significant repair cost but exact amounts not stated in narratives. One LS2-equipped owner identifies oil pan design defect in Trailblazer SS models as cause.
Ignition Switch Failure
Ignition switch fails causing engine stall and inability to restart. Failure occurs at low speeds and recurs after replacement. Multiple repair attempts have not resolved the issue permanently.
When: 28,000 to 55,000 miles
Symptoms owners cite: Engine stalls unexpectedly at low speed (15 mph, 35 mph); All warning indicators illuminated on dashboard; Unable to restart vehicle; Persistent failure after repair
Repairs/costs cited: Ignition switch replacement performed by dealer. Repairs completed but failures recurred in at least one case.
Exhaust Cam Position Solenoid Failure
Exhaust cam position solenoid (variable valve timing) fails, triggering check engine light. Failure recurs even after multiple repairs at dealer.
When: 80,000 miles
Symptoms owners cite: Check engine warning light illuminates persistently; Failure recurs after repair
Repairs/costs cited: Dealer diagnosis and replacement performed multiple times; failure persistent.
Engine Stalling (Undetermined Cause)
Engine stalls at moderate speeds with no warning; cause not determined or variable. One case occurred downhill; another on highway entry. Some failures reproduce consistently, others cannot be duplicated by dealer.
When: 35 to 72,000 miles
Symptoms owners cite: Loss of power at 35-40 mph; Tachometer reading declines during loss of power; Sensation of being pulled backward; Sudden stall without warning; Vehicle unable to restart or recovers after restart
Intake Manifold Crack
Intake manifold cracks. One report at 93,000 miles; owner did not pursue repair or diagnosis.
When: 93,000 miles
Symptoms owners cite: Cracked intake manifold (discovered by owner, not confirmed by mechanic)
Evaporative Emission System Solenoid Fault
Evaporative emissions system vent/valve solenoid circuit failure triggers diagnostic code.
When: Unknown
Symptoms owners cite: Engine check light illumination
Codes mentioned: P0449
Synthesized from 28 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 4 most recent
With only 55,000 miles, the exhaust manifold cracked. Seeing all of the complaints online and talking to my mechanic, this seems to be a default part. Chevy should be recalling these. My mechanic had to order the part through the dealer and they had the replacement manifold in stock. Exhaust manifolds are not normally stock items unless there is a real high need to replace them....... *tr
2008 Chevy trailblazer 42,000 miles had to have the manifold replaced as the entire manifold was split around the entire pipe. *tr
Numerous times I have driven this vehicle and it continues to do the same thing when I reach speeds of about 35 to 40 MPH it loses power, the tach. Even declines in it's reading. It's like someone is behind me with a rope, and stepping on their brakes, slowing me down. This happens when I'm going straight down a street, making no turns, and let it basically idle roll down the street. All the…
Had engine trouble with your 2008 Chevrolet Trailblazer?
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 Chevrolet Trailblazer?
It's a documented issue but not catastrophic. 28 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 23 complaints that reported odometer mileage, most engine failures cluster between 55,000 and 93,000 miles, with the median around 72,000. A quarter of owners report trouble before 55,000; a quarter make it past 93,000. 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/Chevrolet/Trailblazer.
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.