is the SVT Lightning reliable?

The first-gens's had their quirks, but as far as I know the 99+ models were really well built.

Depends on the history of the truck really, how it was driven and cared for.

I wouldn't hesitate to buy one as far as reliability goes. Gas mileage is a different story though.

The only problems with the 99s are they came with a smaller intercooler than the 01+ which was prone to leak, if the owner took advantage of it they were replaced with newer 01+ intercoolers under factory recall warranty so check into yours if unsure.
They had an 80mm Mass Air Flow Meter or MAF instead of the 90mm.
5x135mm wheel bolt pattern and 12mm studs up till 11/99. 99 to late 02 have 3-4 threads in the cylinder heads for the spark plugs. The driveshaft difference. 99-00 3" steel. 01-up 5" aluminum.
You also wana look into a PCV filter. Lightnings are real bad for sucking oil into the intake and coating the impellers with oil which is real bad for the S/C.



So, common problems are gonna be the intercooler leaking, drive shaft vibration, transmition slipping (you will want the Factory Tech Valve Body to make sure it does not happen), repaired (poorly) spark plug threads and broken wheel lugs
Really though they are very good trucks and will last just as long as a F150 as long as you follow the maintenence. If the supercharger is not overspun then @ 80K it should be ready for a rebuild, 50K if over spun.

I don't know too much about them but my ex had a '99 SVT Lightning and modified it. Ran GREAT! I even got to drive it back from the airport after he left for his deployment = ( I was so excited! They are really nice riding and driving in too.

For the most part they are pretty reliable. The F-150 has a nasty habit of filling the plug holes up with water and such, being the motor is pretty far back under the cowl. The cruise control can catch on fire. Recall I believe. I raced my buddy quite a few time. From a dig, we were dead even till 60, then being a fridge, get left behind. He had minor bolt ons. Quick for a truck and most cars at that. Super comfy and I wouldn't look at any L unless it was an 01 or newer.