[JRam08]

I have an 08 4x4 dodge ram 5.7l truck with the 87 perf tune loaded on it. The truck seems to shift like crap now. it surges when driving at highway speeds and between 45-60 like it is having a hard time picking a gear. Any ideas?

 

[RB24]

do you have MDS disabled?

 

[JRam08]

do you have MDS disabled?

No

 

[diablotoona]

Are you running the 9r02 revision?
If you are can you e-mail me your last tune written?
You will have a slight surge due to torque management reduction when mds kicks in and out.

 

[JRam08]

Are you running the 9r02 revision?
If you are can you e-mail me your last tune written?
You will have a slight surge due to torque management reduction when mds kicks in and out.

I can do that tonight I'm currently at work. Should I go ahead and return the truck to stock until you can look over the tune or will that mess up the data you need?

 

[JRam08]

Also I noticed with or without he tuner the RPM's seem to be higher when the truck is in 4cyl mode on the highway, which seems odd to me since the higher RPM uses more gas. Anybody else notice this?

 

[diablotoona]

I can do that tonight I'm currently at work. Should I go ahead and return the truck to stock until you can look over the tune or will that mess up the data you need?

Ok, up to you, i have not really heard of any issues with 08's but that would be your call.
You are running the latest rev 9r02 right?

 

[RB24]

Also I noticed with or without he tuner the RPM's seem to be higher when the truck is in 4cyl mode on the highway, which seems odd to me since the higher RPM uses more gas. Anybody else notice this?

yes, when MDS was not disabled i did notice it ran at slightly higher RPM's and had the surge you are describing. now its smooth as can be

 

[JRam08]

Ok, up to you, i have not really heard of any issues with 08's but that would be your call.
You are running the latest rev 9r02 right?

Yes the latest

 

[JRam08]

yes, when MDS was not disabled i did notice it ran at slightly higher RPM's and had the surge you are describing. now its smooth as can be

When you turned off MDS did you lose the little bit of gas mileage you were getting?

 

[RB24]

no, i actually gained about .5...not much but even if i would have lost 1-2 i would be ok because the sound and surge were enough to make me punch a baby

 

[JRam08]

no, i actually gained about .5...not much but even if i would have lost 1-2 i would be ok because the sound and surge were enough to make me punch a baby

Don't know why but that "ound and surge were enough to make me punch a baby" made me laugh out loud!

I'll give that a try before I go to lunch do I have to uninstall and reinstall it to change the MDS?

 

[RB24]

i am not sure of the steps with Diablo. im sure someone who has it will see this and respond. i have the superchips

 

[diablotoona]

Yes you have to disable the mds then reinstall the tune again.

 

[0212353]

You won't need to set it back to stock prior to doing that though.

 

[chard222]

Mine does the same at speeds between 60-80 depending on the wind speeds. It is the MDS kicking in and out. It runs at a higher RPM when in MDS mode so when it kicks back into 8 cylinders you get a boost feeling or surge. You should feel the same thing when you are rolling to a stop at a stop light, the truck will kind of lurch right before you stop. This is not the tranny. I believe the torque management system determines when it goes in and out of MDS.
Just my $.02

 

[diablotoona]

Well the mds uses a torque management spark table to dampen the "kick" , we alter that table and unfortunately the "kick" is a side effect of altering that since it will not use as much spark reduction to dampen it.

 

[JRam08]

Put it back to stock before lunch. I will re-tune it before I go home and take MDS off to see if it fixes the problem.

 

[392Stu]

Well the mds uses a torque management spark table to dampen the "kick" , we alter that table and unfortunately the "kick" is a side effect of altering that since it will not use as much spark reduction to dampen it.

Thats what that is? Does Lafrad know this? It has bothered us in the past with tuning for performance cams with MDS as you probably know.

 

[diablotoona]

Well i know Mike is having another mds issue mainly on decel and that they kind of get stuck in 4cyl too long.