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4th Gear Billet Servo

mxz905

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mxz905 Enthusiast

mxz905

Posted
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With all the recent vette servo talk a few threads have made mention of the 4th hold servo. Specifically the Sonnax version http://www.oregonperformancetransmission.c...Code=SNX-77767K

 

I haven't come across alot of user input on the 4th hold servo but what I have read seems to consistently report that it eliminates the 3rd / 4th gear searching under load. I had this problem big time until I installed a CAI which made the searching tolerable. (An yes it's possible I just think the CAI made a big difference)

 

Anyhow I'm looking for some input on the Sonnax 4th servo.

1. With 40% more holding power is it going to be a hard shift down under load

2. With that much more holding power am i shortening the life of other tranny components

3. What's normal driving like with no load, do you even notice a difference.

 

My loads typically consist of a double enclosed snowmobile trailer with two sleds and all the gear. In the summer it's a full bed load of building material, camping supplies or firewood. I occasionally tow a 16 foot or 24 foot traevel trailer but that's not very often. Most trips are primarily highway for a couple hours with varying elevations but no mountains.

dlstewart01 Senior Enthusiast

dlstewart01

Posted
Posted

I put one in my 05 GMC because I tow a camper and use overdrive. Every one said don't tow in overdrive so I wanted to beef it up.

 

You will not feel the 4th hold servo as much as you will a Corvette servo. I have a tune with much of torque management removed so I am sure this helped drive ability a bunch.

 

I never get over 190 temp towing even on the hottest summer days. I have the line pressure raised some so I don't use tow-haul. It feels better without it. My trans doesn't hunt for gears hardly at all. I put it in to help the trans last longer. It may be working as I am going on 5 years without any issues.

mxz905 Enthusiast

mxz905

Posted
  • Author
Posted
I put one in my 05 GMC because I tow a camper and use overdrive. Every one said don't tow in overdrive so I wanted to beef it up.

 

You will not feel the 4th hold servo as much as you will a Corvette servo. I have a tune with much of torque management removed so I am sure this helped drive ability a bunch.

 

I never get over 190 temp towing even on the hottest summer days. I have the line pressure raised some so I don't use tow-haul. It feels better without it. My trans doesn't hunt for gears hardly at all. I put it in to help the trans last longer. It may be working as I am going on 5 years without any issues.

 

Thanks dlstewart that's the type of user info I'm looking for. Out of curiosity what size camper are you pulling?

dlstewart01 Senior Enthusiast

dlstewart01

Posted
Posted
I put one in my 05 GMC because I tow a camper and use overdrive. Every one said don't tow in overdrive so I wanted to beef it up.

 

You will not feel the 4th hold servo as much as you will a Corvette servo. I have a tune with much of torque management removed so I am sure this helped drive ability a bunch.

 

I never get over 190 temp towing even on the hottest summer days. I have the line pressure raised some so I don't use tow-haul. It feels better without it. My trans doesn't hunt for gears hardly at all. I put it in to help the trans last longer. It may be working as I am going on 5 years without any issues.

 

Thanks dlstewart that's the type of user info I'm looking for. Out of curiosity what size camper are you pulling?

 

 

Right now, depending on how much the two girls load it up, between 5500 and 6000 lbs.

mxz905 Enthusiast

mxz905

Posted
  • Author
Posted
Right now, depending on how much the two girls load it up, between 5500 and 6000 lbs.

 

Thanks for the info. Weights probably comparible to my travel trailers and about twice my sled and trailer weight. I'm leaning towards the 4th gear Servo, seems to be one of those mods that can't hurt and if I don't like it i can switch back and I'll have a $100 paper weight for my desk.

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