BMW S38B35 engine report, M5 E28
BMW S38B35 · M5 (E28)
3.5 LPetrolInline-61986–1988
84/100
Checked by hand
[good]
Worth having, once the head gasket and cooling are proven
Worth buying, but only on the right car. Records of valve clearance adjustments, timing chain guides in good shape, and a clean history of coolant and oil service.
ExcellentGoodSolidRiskyAvoid
- Known issues
- 4
- Critical
- 2
- Sources
- 17
Verdict
The head gasket is the problem to rule out on an S38.
It is this engine's most common failure, and a critical one. Look for coolant loss and white smoke before anything else, and ask what has been done to the cooling system, because the water pump fails commonly too. Occasionally the oil pump wears or sludges up, which is just as serious, so the oil-change record matters. Chain stretch is occasional, and a cold start is where you will hear it.
Specs
- Displacement
- 3.5 L
- Layout
- Inline-6
- Fuel
- Petrol
- Production
- 1986 – 1995
- Chassis
- E28
- Fitted
- 1986–1988
Known issues
4 confirmed · sorted by severity
CriticalHead gasket failure
Head gasket failure, often preceded by overheating; can lead to a warped head or cracked block if not addressed.
Symptoms
- Coolant Loss
- Smoke (White/Blue/Black)
- Warning Light
How often
Very common · Age-related wear. Does not normally destroy the engine. Not safely drivable.
Evidence
4 owner reports back this, confidence 60/100.
CriticalOil pump wear / sludge buildup
Oil pump wear or sludge accumulation (often from extended oil-change intervals) reducing oil pressure and lubrication.
Symptoms
- Warning Light
- Knocking Noise
How often
Occasional · Owner-caused. Does not normally destroy the engine. Not safely drivable.
ModerateWater pump failure
Water pump seal or bearing failure (mechanical or electric pump), causing coolant loss.
Symptoms
- Coolant Loss
- Warning Light
How often
Common · Age-related wear. Does not normally destroy the engine. Still drivable.
ModerateTiming chain stretch / guide wear
Timing chain elongates or plastic guides wear prematurely, causing rattle, incorrect valve timing, or in severe cases chain failure.
Symptoms
- Knocking Noise
- Cold Start Rattle
- Warning Light
How often
Occasional · Age-related wear. Does not normally destroy the engine. Still drivable.
Check the car you're looking at
Owners rarely say at what mileage this engine's problems start, so they aren't sorted by mileage here. These are the ones to ask the seller about, the ones it's best known for first.
Buying checklist
BMW S38B35 (M5 E28) · Buying checklist
Sources
Updated 15 Sept 2026 · scoring v2.7
Behind this report sit 17 owner posts, forum threads and official records. Nothing gets on the list on one person's word. It takes a recall, or owners on separate platforms describing the same fault. The score then sets how often a problem turns up against the damage it does.