Lot P6744J: 1991 Ford F-250 XLT Lariat

Based on my research, here are the most common problems with the 1991 Ford F-250 XLT Lariat’s 460 engine and E4OD transmission:

Engine Problems (460 CID V8):

1. Exhaust manifold cracks - Very common on these big blocks, especially with age and heat cycles
2. Running rich condition - The EFI system can develop issues causing black sooty spark plugs and poor fuel economy
3. Spark plug fouling - Often related to the rich running condition or oil consumption
4. Exhaust manifold bolt breakage - The bolts can seize and break during removal

Transmission Problems (E4OD Automatic):

1. Overdrive failure - The most notorious issue, with the overdrive light flashing and loss of 4th gear
2. Harsh or erratic shifting - Often related to solenoid issues or low transmission fluid
3. Torque converter problems - Can cause shuddering or failure to lock up properly
4. Complete transmission failure - Many E4ODs fail around 100k-150k miles, with rebuild costs averaging $2,400

The good news is that the truck you’re looking at appears to be well-maintained with only 97,331 miles, and the listing mentions it’s running and driving very well. The E4OD transmission issues were so common that many trucks from this era have already had transmission work done, which may explain why this one is still going strong.

These OBS (Old Body Style) Ford trucks are becoming quite collectible, and despite their known issues, they’re prized for their durability and simplicity compared to modern trucks.

Would you like me to help you find similar F-250s, or do you have any other questions about this truck’s condition or value?