Udate on my jerking Gmax-5

[JShe8918]

So as some of you may know i have been running a Gmax 5 for quite some time now. I was having problems with it slamming into 3rd gear. Well guess what? I took my 37's off and put on my 285's on factory wheels and it is WORSE! I am looking for information to help me get this ironed out. It is now slamming from 1st into 2nd and 2nd into 3rd as well as the 3-2 and 2-1 down shift! I have been driving with no tune since it was first done. They checked the valvebody and they said it looked just like it is supposed too! So what do i need to check next? I thought it was in the valvebody but obviously not. With one WOT run today with my biggest tune, first time having a tune in about 4 months, it heated up to 200 degrees . WTH!!! I am tired of screwing around with the trans shop. They said they had done 5 suncoast kits before and never ran across any problems with any of them. But they were the Stage IV.

This isn't a small bump it is a slam! Like i just broke something or as if the rear end just fell out from under it. It blurs your vision when it slams because it shakes me so much. What do you all recomend trying next?


Jonathan

 

[wsmithduramax]

I just posted on the DF for ya, as did others. If all else fails just get ahold of Mike L. good luck

 

[JShe8918]

I just posted on the DF for ya, as did others. If all else fails just get ahold of Mike L. good luck

Thanks. I have been in touch with both Ron at suncoast and his head builder as well as rob coddens, and Mike L. They all said it was probably a stuck check ball or something along those lines. The trans shop wants to test line pressure and see if it is way jacked up out of specs before they do anything. They wouldn't even pull the valvebody so i had a allison certified friend pull it out and look at it! He looked at the instructions and said it looked right.

Oh and i don't want others to think i am bashing the kit. I know it doesn't have to do with the kit. But rather the installer!

Any help is appreciated. Thanks

Jonathan

 

[SteveFord]

If the clearances are to tight on the clutches would that cause it to slam into gear and on the down shifts?

 

[paint94979]

You need to have an experienced Allison builder inspect the transmission... at the expense of the shop that has obviously built it incorrectly.

 

[gmduramax]

What about trans tune? Rpm vs shift speed?

 

[Mike L.]

If the clearances are to tight on the clutches would that cause it to slam into gear and on the down shifts?

No they would just wear prematurely.

 

[carter_44]

i had a buddy that was having problems with a built trans slamming into 4th gear. turns out it was a fuel related issue. i think it had something to do with the defuel on his tune. he added more fuel and the issue cleared up.

cant explain the tire size or stock tuning on yours though.

i see mike l. viewing the thread so hopefully the boss can fill us in.

 

[Chevy1925]

i had a buddy that was having problems with a built trans slamming into 4th gear. turns out it was a fuel related issue. i think it had something to do with the defuel on his tune. he added more fuel and the issue cleared up.

cant explain the tire size or stock tuning on yours though.

i see mike l. viewing the thread so hopefully the boss can fill us in.

eh, i wouldnt say so yet. just had it hit hard again today though it wasnt as bad as its been. need to put a couple days on it to see how she does.


to the OP. Have you corrected the tire size in the trans as well as the engine to see if that helps? it will throw a abs light but ive seen it help some people

 

[Brayden]

So as some of you may know i have been running a Gmax 5 for quite some time now. I was having problems with it slamming into 3rd gear. Well guess what? I took my 37's off and put on my 285's on factory wheels and it is WORSE! I am looking for information to help me get this ironed out. It is now slamming from 1st into 2nd and 2nd into 3rd as well as the 3-2 and 2-1 down shift! I have been driving with no tune since it was first done. They checked the valvebody and they said it looked just like it is supposed too! So what do i need to check next? I thought it was in the valvebody but obviously not. With one WOT run today with my biggest tune, first time having a tune in about 4 months, it heated up to 200 degrees . WTH!!! I am tired of screwing around with the trans shop. They said they had done 5 suncoast kits before and never ran across any problems with any of them. But they were the Stage IV.

This isn't a small bump it is a slam! Like i just broke something or as if the rear end just fell out from under it. It blurs your vision when it slams because it shakes me so much. What do you all recomend trying next?


Jonathan

Who installed it? Warranty?

 

[IdahoRob]

Tuning can cause issues, but with you running stock tuning for a time while testing removes that option. Stock tcm tuning and stock ecm tuning for a long period of time, shows there is a problem in the build or hard parts IMHO, but I'm not a tranny expert.

 

[JShe8918]

That is correct. I ran stock tuning and Rob suggested i should rule out tuning the first day it was happening. But i think i am going to go down to suncoast in the next month or two and get them to fix it like it is supposed to be.

 

[TIMTHECARMAN2004]

Possible a bad or ripped piston????

 

[03Dmax90]

Get your figured? Mine is having issues aswell. same setup as you but i run 285s

 

[JShe8918]

deleted

 

[JShe8918]

OH and there in another individual with the same problem from the same builder. FYI

 

[Mike L.]

I would be looking at the trim valves. ( Transgo ) I would make sure the balls were in the valves with the springs on top of the balls and the outer spring on each trim valve. I would next measure the diameter of the trim valves and make sure they are not under cut. ( it has happened )
This is a control problem. Let me know if I can help.

 

[JShe8918]

I have a buddy with an extra valvebody but it is out of a LB7... Could i just put it in and see if that corrects it i know that the lb7 and lly valve body has some different selenoids but could i do it for testing purposes?

 

[JShe8918]

And if it is any of the things you just said mike, would it have anyaffects on hard parts such as clutches or anything?

 

[Mike L.]

I have a buddy with an extra valvebody but it is out of a LB7... Could i just put it in and see if that corrects it i know that the lb7 and lly valve body has some different selenoids but could i do it for testing purposes?

If it's an '04 with a G solenoid it will work.