What are some of the issues that come up with running the bigger tunes on these trucks?
I would also like to know the problems that anyone is having after using the spartan tunes.
I will start out with saying I have never ran Spartan tuning. But the opinion I wil share is fairly true to all 'big' tunes.
When you run the bigger tunes with an essentially stock truck (just basic exhaust, intake, and tune mods) you are really cranking the output of the engine up. You are increasing the backpressure between the exhaust valves and the turbo (the turbo will only spool so fast) which is why some guys running bigger tunes and more mods will install an EGR delete with a blow off valve so they can keep those drive essures from overwhelming anything. If you are on a stock trans, you run the risk of damaging that.
Having said that, the majoity of the "problems" associated with the bigger tunes comes down to the truck and driver themselves. How many miles were on the truck before the modding took place? How well has the truck been maintained since new? Are you trying to tow a 10k# trailer on a 310 Race tune? Do you run WOT all the time? Do you keep an eye on your EGTs and other important numbers? The list goes on.
I am not bashing ANY brand of tuning over another, these 'issues' come with any big tunes. I run Gearhead's hottest tune (hottest for a 6.4 without studs and an otherwise stock engine) on my 178K miles truck with no issues. But I pay attention to my gauges and I don't beat on the truck 24/7. Yes, I'll get on it here and there and enjoy the power but I'm not doing drag races and boosted launches from every red light either. When I tow, I step down to a lower power tow tune. Ultimately, there isn't much risk from running a big tune if you drive with sense and don;t expect your mostly stock truck to be a full blown sports car everyday.
One other thing, don;t get disheartened by reading all the horror stories you come across online. Think of how many people are having major issues vs how many people are runnig perfectly fine while tuned vs how mny of these trucks are out on the road. Not too many people go out of their way to jump on a forum site just to say "Hey, my truck is running perfect and I've never had ny issues" most people come to forums looking for help with a problem!