Downside to installing the Corvette Servo?

[TogaPC]

When I bought my hoe, I knew that I was going to have to rebuild the tranny before too long. Sure enough, after 130k miles the sun shell broke and I paid $1800 for a rebuild. The guys that rebuilt it are strictly a trans shop and they have a really good rep around town of being honest and for doing quality work. I asked the head mechanic if they would put a vette servo in while they were rebuilding and he refused. He said that the shifts would be way to firm and that I would hate it.

A few weeks after the rebuild I ordered my servo from Oregon Performance and after 2 hours and 8 beers, it was installed. I was a little leery at first because the shifts were really firm and I didn't want to break anything.

Called Justin at Blackbear and he adjusted my tune to allow softer shifts normally and really firm shifts in sport (tow / haul) mode. My shifts are now noticeably quicker than before but not uncomfortable.

It's been close to a year since then and I have had zero problems so far. Any mechanic is going to have the opinion that if It ain't broke don't fix it so you'll probably have a hard time convincing your dad it's for the best.

That being said...lets all be honest here, in the end it's not really about getting better gas mileage or improving the reliability. It's about making a 3 ton brick as sporty as we can so it's more fun to drive. Who doesn't like the sound of a growling exhaust or the chirp of the tires on a second gear shift. It will never be a sports car but it doesn't have to be a dog either.

Tell your dad the honest truth, you want to make the shifts firmer and this is an easy way to do it that doesn't seem to really cause any problems.

Good Luck.

 

[Dberdusco]

As a transmission re builder I would advise against it unless it is put in after a overhaul.... Reason bieng is that the original sun shell in these 4l60e units is so soft they end up stripping with a oem servo.... So you add a servo with a greater apply área like a corvette servo it creates a firmer shift... That in turn puts more torque on the sun shell during the 1-2 shift because it is bieng stopped with more force it will snap sooner.... Unless it has a hardened shell or a sonnax super shell that will resolve the issue with the sunshell snapping

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[TogaPC]

As a transmission re builder I would advise against it unless it is put in after a overhaul.... Reason bieng is that the original sun shell in these 4l60e units is so soft they end up stripping with a oem servo.... So you add a servo with a greater apply área like a corvette servo it creates a firmer shift... That in turn puts more torque on the sun shell during the 1-2 shift because it is bieng stopped with more force it will snap sooner.... Unless it has a hardened shell or a sonnax super shell that will resolve the issue with the sunshell snapping

Sent from my SPH-D710 using Tapatalk 2

+1...OEM Sunshell and Planetary's are crap. 5 pinion planetary and the beast sunshell in mime. You gotta pay to play.

 

[04ctd]

this all makes sense. my tranny guy would NOT firm up my shifts on my ~90k mile tahoe.
said it just makes problems.

said he would do it on the rebuild, he said a rebuild could be as low as $1300 if i was lucky.

 

[josueh95]

this has me thinking about getting one for mine..never heard of this upgrade until now

 

[a4edwin]

Did the op ever instal it?

 

[FrankU]

I have 155K on a 2006 5.3 4X4 Police vehicle. It will be used to tow @ 5K aluminum car trailer.
The 480LE would probably be overkill for this weight. Who builds a good 4L60E 4X4 without spending 5K ?

 

[TxTooTall]

start look for a 40K Tru Cool tranny cooler . . . makes a huge difference also. . . . add it in line with the stock radiator cooler.

 

[FrankU]

Thanks Tex

 

[Sean James]

I've always wanted to install one, cheap and easy upgrade. BUT, I have had TWO (2) Tahoe's shatter the sun shell's without any modifications. Both were factory transmissions 4wd's. One was a '98 with the manual shift 4wd, and one was a '99 with the push button 4wd. The '98 Tahoe grenaded the the sun shell at 209,000 miles. The '99 grenaded the sun shell at 217,000 miles.

The '98 towed a quad on a 5X8 box trailer maybe 10 times at most. The '99 never towed anything. Both came with the tow package and factory trailer hitch mount. I noticed the '98 searching in overdrive on the tach going from 1300 rpm to 1400 rpm for a year or so before the reverse gear went, and an hour later the whole trans quit (sunshell cracked apart).

Both were purchased used with low miles around 90-110,000 or so, and factory bone stock as far as I know. My wife and I babied both of them the whole time...maybe that was the problem. So now, I fear the 4l60's will strand me. Both were sold as is with blown trannys, the shop out here in our small town wanted 2,600$ to rebuild the trans in either one. So we sold them.

I figured I got over 100,000 miles out of both of them, and paid exactly the same for each $2,500. So I guess I got my money's worth. Then my wife finds another one, and I find a Yukon, both '99's for the same price $2,500 again! Kinda wierd, but we took the chance. Probably going to end up with the same scenario. But this time, I changed the trans filters and complete drain and fill with valvoline max. Installed a drain plug on each truck, and installed larger trans coolers on both. But until I get the upgraded sun shell, I don't think I will install a servo or shift kit. Call me tranny shy!