Stickied: 4L70E - worth a look? - Chevy Impala SS Forum
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 16 (permalink) Old 02-17-2012, 09:06 PM Thread Starter
Senior Member
 
Dan Fahey's Avatar
 
Join Date: Jan 2001
Location: Germantown
Posts: 3,178
 
Stickied: 4L70E - worth a look?

GM has introduced a 4L70E transmissions..

Is this a good replacement tranny fro the 4L60E?
OR
Better to upgrade the 4L60E

D
Dan Fahey is offline  
Sponsored Links
Advertisement
 
post #2 of 16 (permalink) Old 02-17-2012, 10:01 PM
Senior Member
 
Join Date: Jul 2004
Location: IL
Posts: 1,040
 
waste....they dont even have a vette servo. I believe it has the 5 pinion planetaries. Either way they are going on 6 yrs old.(so they have been out for awhile)Just build your 60 up better. IMO

96 BBB CAI spintech ss304 exhaust,Tri-ys, Hotchkis everywhere,3:73s with eaton, 1.6cc/ls2 springs, black imp rims,dennys d-shaft,
98 Lumina 9c3, beater sold!
06 Impala magnaflows k/n
96 9c1 gone, not forgotten
96 BBB sold
ISSCA #2461
Bowtie 9C1LT1 is offline  
post #3 of 16 (permalink) Old 02-17-2012, 10:15 PM
Senior Member
 
wytltng's Avatar
 
Join Date: Nov 2009
Location: Southeast Mi
Posts: 4,753
 
Why not upgrade to a 5sp allison?
wytltng is offline  
post #4 of 16 (permalink) Old 02-17-2012, 10:50 PM
Senior Member
 
Join Date: Jan 2003
Location: San Diego
Posts: 2,799
 
Quote:
Originally Posted by wytltng View Post
Why not upgrade to a 5sp allison?
Can you expand on this? Sounds interesting. Experience, links, conversion, etc?

Forum search and Stickys came up empty.

grandpas wagon
1994 RMW 69K, clear corners, Gary's cables - battery, headlight, mech fan delete, air pump delete, home plate/first base delete, Bill Harper wiper arm mod, Corvette starter, 1LE elbow, Team SS pipe, K&N filter swiss cheese airbox, throttle body bypass, AutoMod Atlanta headlights.

All my posts contain 100% recycled electrons.

Last edited by grandpas wagon; 02-17-2012 at 10:54 PM.
grandpas wagon is offline  
post #5 of 16 (permalink) Old 02-17-2012, 11:21 PM
Senior Member
 
Mr pogo's Avatar
 
Join Date: Oct 2003
Location: SoCal
Posts: 6,358
 
I doth thinketh he was being sarcastic

evil T-47 seatbelt bolts and cutdown ZQ8 bumpstops, Kore3 front brakes, TB bypass, Dynotech DS, F-body EGR, Meziere WP, Comp Cams 1.6RR/CM springs, trans by Moi Industries, Yank 3600, Earls trans cooler/rad cooler delete/Derale t-stat, RAISS, SLP headers, SLP injectors, pypes X-pipe/magnaflows, Borgeson shaft, Hotchkis springs, PPM front stuff, Metco rear arms, Clear Image DS loop/trans crossmember, 3.73s, eaton posi, Hypertech for smog \"[<img BH tuned PCM
Mr pogo is offline  
post #6 of 16 (permalink) Old 02-18-2012, 05:57 AM
Senior Member
 
wytltng's Avatar
 
Join Date: Nov 2009
Location: Southeast Mi
Posts: 4,753
 
Quote:
Originally Posted by Mr pogo View Post
I doth thinketh he was being sarcastic
Not true. In this case. I can be at times.
I have a 5sp allison in my 2500HD. It bolts right up to the 8.1 & has its own dedicated computer. I know these trans could handle the torque an power we want to put behind them.
I would be interested in seeing if these would work.
Maybe Shane has some insight.
I know they are not cheap used.
wytltng is offline  
post #7 of 16 (permalink) Old 02-18-2012, 06:14 AM
Senior Member
 
Navy Lifer's Avatar
 
Join Date: Nov 2000
Location: Canton GA/Poway CA
Posts: 6,214
 
GMPP catalog - page 152 to 156 gives full details.

I think 4L70 was designed for use behind LS engines--the crank/flex plate position difference may prevent it from being a bolt-on for the GenI/II blocks--there is an adapter package that provides the ability to use later GenIII/IV transmissions on conventional small blocks, including LT1, but it's not 100% clear in the way it's listed as far as the 4L70.

I'm thinking the sheer size of the Allison 5-speed may prevent it's use in the car, without cutting out the tunnel/floor at the firewall and making a new one. Trans crossmember position would probably be different, too, as well as a number of other things--and just like the rest of the Gen III/IV transmissions, an adapter setup would be necessary.

The 4L70 is rated for 495# torque--it should handle just about anything that can be thrown at it.

Bill Harper
ISSCA #127
inov8r@windstream.net

Last edited by Navy Lifer; 02-18-2012 at 06:22 AM.
Navy Lifer is offline  
post #8 of 16 (permalink) Old 02-18-2012, 06:24 AM
Senior Member
 
Mr pogo's Avatar
 
Join Date: Oct 2003
Location: SoCal
Posts: 6,358
 
Quote:
Originally Posted by wytltng View Post
Not true. In this case. I can be at times.
I have a 5sp allison in my 2500HD. It bolts right up to the 8.1 & has its own dedicated computer. I know these trans could handle the torque an power we want to put behind them.
I would be interested in seeing if these would work.
Maybe Shane has some insight.
I know they are not cheap used.
3 reasons why not for b-bodies.
too big
weighs too much
high parasitic power loss

not to mention lack of performance converters and gearing may not be optimal for performance and other things along that line.

evil T-47 seatbelt bolts and cutdown ZQ8 bumpstops, Kore3 front brakes, TB bypass, Dynotech DS, F-body EGR, Meziere WP, Comp Cams 1.6RR/CM springs, trans by Moi Industries, Yank 3600, Earls trans cooler/rad cooler delete/Derale t-stat, RAISS, SLP headers, SLP injectors, pypes X-pipe/magnaflows, Borgeson shaft, Hotchkis springs, PPM front stuff, Metco rear arms, Clear Image DS loop/trans crossmember, 3.73s, eaton posi, Hypertech for smog \"[<img BH tuned PCM
Mr pogo is offline  
post #9 of 16 (permalink) Old 02-18-2012, 11:37 AM
Banned
 
Join Date: Jan 2012
Location: Newark, Delaware
Posts: 278
 
The 4L70E has no performance advantage over a 4L60E. I update my "Race" and "Pro Race" 4L60E's with certain 4L65E parts to add strength. As far as an Allison? Great TRUCK transmission, but as already stated, it's too big and heavy to have any benefit in a performance vehicle. This closely related the the misconception that a 4L80E is a good performance transmission. We had a few hard headed customers 15 years ago that thought the 4L80E would be better than a 4L60E. EVERY car we built them for slowed down ATLEAST 2/10's in the quarter mile. We ended up swapping most back to '60E's...Or the customers got so disgusted that their cars were now turds that they sold them.

Frank
cahall is offline  
post #10 of 16 (permalink) Old 02-18-2012, 12:18 PM
Senior Member
 
Join Date: Dec 2004
Location: Fishers, Indiana
Posts: 1,252
 
Quote:
Originally Posted by cahall View Post
The 4L70E has no performance advantage over a 4L60E. I update my "Race" and "Pro Race" 4L60E's with certain 4L65E parts to add strength. As far as an Allison? Great TRUCK transmission, but as already stated, it's too big and heavy to have any benefit in a performance vehicle. This closely related the the misconception that a 4L80E is a good performance transmission. We had a few hard headed customers 15 years ago that thought the 4L80E would be better than a 4L60E. EVERY car we built them for slowed down ATLEAST 2/10's in the quarter mile. We ended up swapping most back to '60E's...Or the customers got so disgusted that their cars were now turds that they sold them.

Frank
DEAD ON!! I use some 65 and 70 parts in the 60 but thats all you need.

I guess only racers think about power loss but if you care about ET then you better care about power loss. It's easier to not have to figure out how to make more power when you can reduce power loss behind the engine. A 4L80E eats power and you cant make up 2 tenths in a better 60 foot launch so even a slower 60 foor by a little will result in a faster ET in the full run.

Ramdom thoughts but thats one reason a 60 is still in my car.

LTX Aluminum LT1 block engine
Most HP from an OBD1, 1900 plus horse power
Only TH400 with lockup and shifts from factory GM computer
Fastest Impala with everything still in it, 4520 pounds no weight taken out. ? in the ? MPH
Jeff Green is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevy Impala SS Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome