Corvette Servo install for firmer shifts in Silverado, Sierra, and other GM vehicles.

[@shuriKen469]

cheers for sharing what you could mate! gonna tackle this at some point when i'm not lazy and this'll be one of the removal/assemble/install videos i'll go off of.

[@MNJLLC]

I don’t even use tow mode when I’m towing…😅

[@wbmjr46]

Tow Mode is designed to hold the shift longer allowing you to get whatever you are hauling moving quicker.

[@budthechud3408]

Is there an upgrade to the large spring that goes in first? Anyone got a part number?

[@LaserLuther]

The servo has more area for fluid to push on there by applying more force to the 2-4 band giving firmer shifts into 2nd and 4th. This is great for towing in overdrive.

[@michaeldose2041]

Actually that is incorrect. 4th gear is applied via the piston in the outer cap. If that is stock you are modifying second gear apply pressure only. Sonnax makes a different cap, which has a bigger inner bore, not a lot bigger because it is limited by the size of the case bore. When towing, don't be afraid to downshift on a hill and hold it in third gear. I believe GM designed this transmission to come out of 4th easily. Overheating occurs when the transmission shifts between 3rd and 4th excessively. In that case I just hold it in 3rd until I am back on level ground. Hey these things aren't idiot proof.

[@blaine4202]

How is it shifting after long term

[@budthechud3408]

Is this applicable to a 2004 GMC Yukon 5.3L with 4L60e and AWD?

[@tylerhilton03]

Yes bob.

[@Jermaine743]

Trying to figure out why everyone keeps taking it apart

[@eloytorres5480]

After the servo pin is removed, there is a spring that needs to be changed between the cups

[@MeaHeaR]

Great Vidd 👍👍👍

[@danieltidwell6380]

Bruh u had towmode on of course it’s gonna hold for longer lol

[@QQTrick1QQ]

Tow mode just makes it a 3 speed eliminating 4th gear so it doesn't keep shifting back and forth.

[@johnmills837]

Not even close Bozo

[@Highstranger951]

Wow, people know so much...🤣

[@splash5974]

I spent an hour last night trying to get the servo cover pryed in enough to remove the clip. Was impossible! Your cover moved in with no effort. Mine is stuck! Finally gave up an hour later, with scraped up knuckles... Anyone have any suggestions? Not enough room to get a hammer in there and tap the cover.

[@imjeremy51]

I dont know man. Did you try a pry bar using the tunnel as the fulcrum? Maybe wack the prybar with a hammer? It should just be pushing against the spring, unless there is some grime in there? Maybe some atf in the groove around it to loosen things up? I wouldn't use any brake or carb cleaner incase you still cant get it off you dont want to destroy the o-ring. I also wouldn't use any chemicals you dont want in your atf... I would stick to ATF and a prybar, maybe a hammer to the prybar to shock it loose.

[@splash5974]

@@imjeremy51 ya, i got a pry bar up in the same location. My truck is identical to yours. I used some spray lubricant around the cover, but it just doesnt move in at all. I can move my trans and exhaust, but not the cover. Even tried channel locks on the cover, but im afraid to snap the cover. I wonder if i just try and pry the snap ring off the way it is, then try and loosen the cover free? Don't know why its so seized in place...

[@imjeremy51]

@@splash5974 I wouldn't try to get the snap ring out while the cap is up against it. The snap ring can't physically come out with it there (I dont think). If your really determined I would consider removing the exhaust so you can get to it. I would use a rubber mallet or be very careful against the aluminum housing/cap though.

[@chrisao1987]

I'll just limp it along till it dies. How about servicing the trans when you supposed to 🤷🏻‍♂️. Also, why the hell are you driving in tow mode?🤦🏻‍♂️.

[@Devo1987]

so will this speed up the shifts going up hill's make it move thru gears sooner ?

[@imjeremy51]

Doesn't change shift points, thats controlled by the computer. It applies more pressure to the 1-2 bands, the transition between gears is quicker, but the point in the rpm range doesn't change.

[@jorgevega4325]

Is it a good idea to install a servo on a non built 4l60 on my 2000 Silverado? A friend of mine gave me a servo he ended up not using and was wondering if this has any pros? Any things I should know before installing?

[@hollygrovegeedy4849]

there was zero reason to put tow haul on thats for when your pulling a load so if you wanted to see how that changed shifting on tow haul should of connected the camper 🤣

[@chefzackkasmar6767]

How is the truck shifting now? Still running and shifting firm?

[@michaeldose2041]

The servo applies pressure on the band, not the clutches. The band is a weak point and the extra pressure is achieved by making the center section smaller, giving the apply piston more surface area. The band applies in 2nd and O.D. or 4th. Notice that the center section of the servo moves independently from the outer piston. The outer piston is located inside the cap that you see from the exterior of the trans. The outer piston applies pressure on the band when in fourth gear. When the user installed this set up he would be increasing pressure on second gear band apply only. Sonnax has a larger outer piston to increase pressure in fourth gear as well. I mention that because the band is a weak link and it can slip in fourth as well as second. Given the fluid color of this transmission I would say you may very well have some band slipping going on. Obviously it is best to make this mode before that begins to happen.

[@DerrickRG]

Michael Dose He mentioned in the description that the 700r4 needs the whole pin, why is that?

[@michaeldose2041]

The servo applies pressure on the band via the apply pin. GM has three different lengths of pins. It is critical that after installation of the servo that the travel is between .120 and .070 inches. That is measured by installing the servo and then pushing in on the cap from outside of the transmission until you can feel it bottom out. That is a little tricky to do because you are pushing against cushion spring behind a washer on the second gear apply. That is critical because 4th gear is being applied via the piston inside the cap. There is only about .250 of travel inside the cap, so you need to be sure it's inside that range to get full apply on 4th. 2nd on the other hand is using the bore in the case so it has much more travel available. If you fall below the lower limit you can grind the pin down. Sonnax has directions on how to do that using a washer as a circumference guide. Obviously if it needs to be longer you will need a different apply pin. Short question, long answer hope that helps. One more note if you are not modifying the outer cap and only changing the inner second gear (assuming a new band is installed) servo your clearance shouldn't change.

[@splash5974]

So is it a bad idea to install a Corvette style servo on a trans wuthout building it first? You seem very knowledgeable, i ask because i would like to install a servo on my Sierra with the 4l60e. I find the trans pretty lazy between shifts, even at normal throttle position. Ive done a trans filter and replaced the fluid. I had the truck test driven by someone i know at the dealership, and they say its normal, and they are designed to slip slightly, in order to get a better driving experience. I say BS, and they probably do that so transmissions dont last over 10 years... Thank you

[@brendonnz1964]

Need Transmission Fluid change

[@packingten]

A LOT of hd truks&4x4 have vette servo

[@SmudgyContent]

Is ur transmission still going?

[@james10739]

Ya mine had the bur too i just put it on the press but I did not realize it should come out till after i had the other clip out ot would have been easier but its done now

[@mobleyMobley]

Wow, very informative video.... Lol!!

[@porfiriohernandezjr3570]

Great video. Do you have to deactivate stabilotrak and put it in tow mode for the servo to work?

[@imjeremy51]

Porfirio Hernandez Jr no, it firms up the shifts regardless. It just applies more pressure to the clutches. The tow mode and shutting off stabilitrack just changes the shift points, and doesn't automatically let off the throttle if the tires break loose.

[@billmonroe8826]

@@imjeremy51 Actually it applies the band and holds it more firmer because the servo has a bigger area than the old. But since this was 3 yrs ago and by the looks of your fluid, you have probably overhauled the tranny by now as the 3-4 clutch is one of the weakest points in that transmission.

[@imjeremy51]

@@billmonroe8826 actually somehow the tranny is still kicking. However, I am about to put a built 6.0 in front of it so I can give the trans a proper send off.

[@5150on420]

Fix your damn camera to something. We obviously you're not looking at what you're looking at

[@joeh4253]

The only piece of good info from this whole thing is @michael dose comment. Top notch info, there. The video is garbage and def not a install, tutorial, or anything of the sort.

[@jorgevega4325]

Is it a good idea to install a servo on a non built 4l60 on my 2000 Silverado? A friend of mine gave me a servo he ended up not using and was wondering if this has any pros? Any things I should know before installing?

[@blacknbs3482]

Yes help the clutch packs out in the end

[@obfuscated3090]

YES. I have one and it shifts much better with no shift flair. I also installed a Sonnax pinless accumulator since the stock garbage tended to stick.