scott_mckinney

Hey Guys. I am looking to upgrade my 07 Tahoe drivetrain as much as possible. We have dropped a new LS7 engine in my vehicle and need to do everything possible to prevent any future drivetrain issues. What tends to be the weakest links on these models? What can be done or upgraded to prevent any issues? Please advise.

ZX1100F1

Scott,
Your Tahoe has an 8.6" (actualy 8.625" if you need exact) some call it an 8.5" but that is not correct, it's like the people that refer to the new 5.3L Vortec engine as a 327ci which it isn't

You will pretty much have problems with everything aft of the engine crank with your set-up, some components lasting longer than others.

The Suburban, Avalanche etc with the 6.0L or 6.2L engines use heavier duty components, these parts including the 9.5" rear-end should do a much better job of handling your new found horsepower, I am not aware of any aftermarket company that makes high performance drivetrain components for the GMT900 Tahoe at this time.

I'm trying to get a spline count and length on the axle however we currently don't have one torn down in the garage, and I am working on different projects now days.

kpanza

Ouch, your drivetrain will hate you! The poor 4L65E trans will likely not last long with that much power...even the 4L80E version will not enjoy life...I'm sure you can contact an aftermarket tranny shop and they can build you something that will at least last longer than factory...

Like ZX said, your 1/2 ton axle will also hate you. You need to upgrade to at least the 9.5" of the 3/4 tons...for pure beef, one of the 11.5s out of the Silverado HDs with the Duramax would be the end of all your worries...the old 10.5 14 bolt would be great, but doesn't have any of the ABS or electronics you'd probably need...

Most of the issues nowadays are related to getting all of the electronics to "talk" to each other and all get along (ABS, stability control, ECUs, Trans modules, etc)...sounds like a fun project! I guess you could just drive it til something breaks, then start upgrading those parts?

e

ls7 NICE.........Im justa little suprised that your just now looking into setting up the chassis and powertrainfor thiskind ofpower. Anyway im not trying to hate, im all about the power, but if your taking a brand new truck and making these kind of additions it would seem thatmore time would of been spent into making the ride fast, safe, and reliable.Have fun with the powerhouse and my input for your project would be to STOP, as in brakes baby........BIG ONES.

ZX1100F1

A big problem with bolting up any rear axle larger then an OEM 9.5" is the fact that the Tahoe has rear coil springs and the HD trucks and Suburban's use leafs with different housing mounts, the 8-lug wheel requirement would also throw a monkey wrench into the mix, you can get adaptors but not anywhere near the correct offset.

Probably will need to have a rear-end custom fabricated.

scott_mckinney

Hi. Alright, thanks for the information. Is there any difference in the 2007 rear end and components, as compared to earlier year GM 8.5/8.6" models? I currently simply need to know the axle length, the splines are 30 spline, but I am un-sure of the factory axle length. Does anyone have this information? Please advise.

ibcheeky

Scott, The people at Redstar Performance built a LS7 Tahoe and could probably answer any questions you may still have. They have videos on their site of their07 LTZ Tahoe running at a drag strip and blowing the doors off aLS6 Z06 Corvette. I would assume modifications were done to the transmission and rear end.

RedstarPerformance

scott_mckinney

Hi. Redstar performance built my LS7 machine but the drivetrain just doesnt hold up.
Any other suggestions or comments from anybody? What about these transfer cases?

SWRidin

That sucks... Sounds like you didn't get what you paid for. They should have already had those issues worked out.

sbrug

Scott,

My next door neighbor is quite the auto enthusiast and is very familliar with the LS 7 engine. He stated that you need to contact the guys at RPM transmissions. They should be able to build what you need. http://www.rpmtransmissions.com/ just give them a call.

Good luck