I have been running the spartan 210 and 250 on my truck for months. The truck from day 1 with these tunes has had a bucking problem around 60-70mph.After finding out this is a common problem I started looking into it and found that tractions bars would be helpful because my truck is lifted with 37"tires. Well, I just installed my new traction bars and while it took care of all hesitation,it still bucks and I am tired of it.Has anybody that has used the Spartan and Blackmaxx had the same problems with the Blackmaxx tranny bucking?

 

Try River City Diesel Tunes, I've ridden in the owners personal truck and his is a monster and never has any problem even with the lift and large tires, Id be glad to help you out if you need advice, just hit me up
Jared @ RFFI

 

that is a common problem in tuned (spartan/sct etc..) trucks as well as some stock trucks. mine does it only in cruise control

im kinda curious to see what can be changed in the programming to help fix it

 

Guess that's one of the few problems I never had with my truck. I know on the spartan site prople were complaining about bucking int the 310 and 275 tunes but they said it had something to do with it defueling iirc

 

This sounds exactly like the problem I'm having. With my SCT tune in (performance) it bucks at 110k (70mph). I took the tune out, changed my fuel filters & still bucks at the same speed.
Took it back to the dealer, tech plugged his laptop in & away we went. #2 & #6 injectors were weak. But they won't replace them under warranty because they are only in the 5% below normal range. The injectors on either side of these weak ones pick up the slack to even out the engine so it won't run rough.
This can't be normal?
With 148000k on this truck I'm running out of warranty soon and I don't really want to have to pay for a repair that should have been done under warranty.
Any thoughts? Comments?

 

I just got some great news in response to my above "bucking"problem on the higher Spartan tunes.As of 2-15-10 Spartan will release the updated 250-275 and 310 tunes which they are saying will take care of the surging/bucking problem. Man I hope it works!!!!

 

Let me know what happens. I did an update on my SCT and she still bucks at 110k.