C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

Maintance Questions...

Thread Tools
 
Search this Thread
 
Old Jan 16, 2013 | 06:53 PM
  #1  
Snaps's Avatar
Snaps
Thread Starter
Racer
15 Year Member
All Eyes On Me
Photogenic
Liked
 
Joined: Feb 2009
Posts: 492
Likes: 19
Default Maintance Questions...

Info: 1990 6speed

Questions:
1: What kind of Fluid should be used in the Trans
2: What kind of Fluid should be used in the Rearend

Any tips when replacing the Thermastat, Flushing the coolant, and rearend fluid?

EGR block off plates... Removing the EGR and blocking them off would that require a tune?
Reply
Old Jan 16, 2013 | 10:34 PM
  #2  
Churchkey's Avatar
Churchkey
Melting Slicks
10 Year Member
 
Joined: Sep 2008
Posts: 2,376
Likes: 111
From: Cherokee National Forest TN
Default

Fluid brands vary depending on user.

If M6 remove the fill plug before draining the trans to insure refill.

No drain plug in the rear end. Warm the gear oil & suck it out.

Egr block will get a CEL code 32 (EGR), the only way to remove the CEL: Burn a new chip.
Reply
Old Jan 16, 2013 | 10:45 PM
  #3  
ghlkal's Avatar
ghlkal
Safety Car
Supporting Lifetime Gold
20 Year Member
Community Builder
Community Favorite
Top Answer: 3
 
Joined: Mar 2005
Posts: 4,471
Likes: 1,224
From: Fredonia WI
2025 Corvette of the Year Finalist - Unmodified
2024 C7 of the Year Winner - Unmodified
2023 C4 of the Year Finalist- Modified
2020 C4 of the Year Finalist - Modified
2019 C4 of Year Finalist (performance mods)
2018 C4 of Year Finalist
Default

Originally Posted by DriftaVette
Info: 1990 6speed

Questions:
1: What kind of Fluid should be used in the Trans
You'll get lots of opinions.

I use Castrol TWS 10-60. You'll find it at BMW dealers.

Reply
Old Jan 17, 2013 | 09:48 AM
  #4  
Snaps's Avatar
Snaps
Thread Starter
Racer
15 Year Member
All Eyes On Me
Photogenic
Liked
 
Joined: Feb 2009
Posts: 492
Likes: 19
Default

Thanks for the input.
Reply
Old Jan 17, 2013 | 10:43 PM
  #5  
93Rubie's Avatar
93Rubie
Safety Car
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2010
Posts: 3,752
Likes: 190
From: Indiana PA
Default

Amsoil Syncromesh? is popular so is the Castrol TWS 10-60.

Some of use (me included) run Redline Lightweight Shockproof Gear Oil aka Smurf Blue.
Reply
Old Jan 19, 2013 | 08:42 AM
  #6  
C66 Racing's Avatar
C66 Racing
Premium Supporting Vendor
20 Year Member
Conversation Starter
All Eyes On Me
Top Answer: 1
 
Joined: Aug 2001
Posts: 5,364
Likes: 38
From: King George VA
Default

Originally Posted by DriftaVette
Info: 1990 6speed

Questions:
1: What kind of Fluid should be used in the Trans
2: What kind of Fluid should be used in the Rearend
AMSOIL offerings for your 90 6 speed:
Tranny: AMSOIL Synthetic Synchromesh Transmission Fluid (MTF) (Product Code MTFQT)
Diff: AMSOIL Severe Gear Extreme Pressure Synthetic 75w90 (Product Code SVGQT)

More than happy to get AMSOIL products for forum members at dealer wholesale pricing, about 25% below retail, via the AMSOIL Preferred Customer Program. Drop me a PM if interested.

Good luck with the fluid swaps!
__________________


C66 Racing #66 NASA ST2, SCCA T2
AMSOIL Dealer (Forum Vendor)
AMSOIL Preferred Customer Program (Members buy at Wholesale - a savings of about 25%)





Reply

Get notified of new replies

To Maintance Questions...





All times are GMT -4. The time now is 07:09 PM.

story-0
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-1
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-2
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-3
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-4
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-5
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-6
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-7
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-8
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-9
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE