4L60E Servo Upgrade

[dps01]

Apologize in advance if this has already been covered. Checked the forums but did not find the answers.

Finally ready to pull the trigger on a BB tune for a 2003 Z71 with ~240K miles on original L59 engine and transmission.

Will be enabling electric fan capabilities with the tune and figured the Corvette servo upgrade should be done before gathering the data for the tune.

Looking for better drivability (seat of the pants dyno) but without sacrificing reliability / durability.

Is this a bad idea with present mileage?
Is a specific Corvette servo recommended or any to avoid?

 

[justirv]

Apologize in advance if this has already been covered. Checked the forums but did not find the answers.

Finally ready to pull the trigger on a BB tune for a 2003 Z71 with ~240K miles on original L59 engine and transmission.

Will be enabling electric fan capabilities with the tune and figured the Corvette servo upgrade should be done before gathering the data for the tune.

Looking for better drivability (seat of the pants dyno) but without sacrificing reliability / durability.

Is this a bad idea with present mileage?
Is a specific Corvette servo recommended or any to avoid?

I feel that a stronger shift (from servo) will send your trans to the grave quicker. You have been fortunate that you made it past 200k. It may be time to really take advantage of your tune and look at getting a performance rebuild(?). If/when that time comes, recommend looking up Sonnax build sheets for the hard parts to reach the level of performance you're looking for.

 

[Joseph Garcia]

Talk to the folks at @BlackBearPerf , and they should be able to give you some advice regarding risk factors. I didn't think twice at 130k miles for a tune, but that's a long way from 240k miles.

 

[Marky Dissod]

'corvette servo' is a misnomer. Every 4L60E behind a V8 gets the same so-called 'vette servo'.
However, the 4L60E behind a 4.8L V8 is built a bit differently vs one behind an LS2 (clutch pack arrangements).

Talk to your rebuilder, ask about the difference between having your 4L60E rebuilt to withstand an LS2
(similar to 4L70E) vs having it rebuilt to chronically tow 8,500lb.
Idea is to rebuild it sacrificing 1MpG in exchange for more durability / longevity. It'll shift a bit more firmly,
but not offensively so; your passengers might not even notice.

FairBanks servo is necessary IFF you plan on HEAVY towing / hauling or hard racing, otherwise optional.

Just checking, but did you forget 3.73 vs 4.10?
Long story short, if you heavily favor highway MpG, stick with 3.73, but ...
if you heavily favor stop'n'go metro/urban MpG, or plan on racing hard / working hard / towing heavy, 4.10.
All other things equal, 4.10 is about a year's worth of durability.

No, it's not a bad idea with present mileage - should've done it sooner.
Explain to your tuner what you want from your tune, whether BlackBear, PCM Performance, or whomever.
Point is your tune is your burger, do your due diligence so you can have it your way -
it's not a cookie cutter process (unless you settle for that, so don't).

*If you've NO plans to tow / haul, consider having your Tow / Haul shift map tuned like a 'Performance' shift map.
3.73 is still my main limitation by far, but when I press that button, it becomes much more fun to drive like an arse.

 

[dps01]

Thanks for your insight.

Gearing is 3.73 w/ no plan on changing that.

The tune has been on the wishlist for years…

Main use these days is long trip family hauler (2500 mi. trip 2X /year) and tow a car trailer occasionally.

Durability / reliability is foremost, and I don’t mind the harder shift. Not looking to smoke the tires…have a GN for that .

 

[Marky Dissod]

Thanks for your insight.
Gearing is 3.73 w/ no plan on changing that.
The tune has been on the wishlist for years …
Main use these days is long trip family hauler (2500 mi. trip 2X /year) and tow a car trailer occasionally.
Durability / reliability is foremost, and I don’t mind the harder shift. Not looking to smoke the tires … have a GN for that .

In which case, be sure to ask your tuner to improve the Tow / Haul shift table as well.
Once you get the tune done, you'll wish you'd done it sooner,
and preach its gospel on to a bunch of people who will misunderstand and wave it off ...

 

[dps01]

Once you get the tune done, you'll wish you'd done it sooner,
and preach its gospel…

Copy That !