GM 4T40-E
GM 4T40-E
I'm new to auto transmissions but am currently in the process of converting a twin engine car which i've built from manual transmissions to automatic transmissions due to the problems trying to shift 2 manual boxes consistently and quickly.
The only transmission that I have been able to get into the small space is the GM 4T40-E (and this has been hard to find a source of in the UK).
I believe that this transmission is similar to the GM L series in function and was wondering if there had been any plans to get this transmission added to the supported list.
Although i'm new to auto transmissions I am reasonably skilled with electronics and mechanical design so hopefully will be able to pick up the knowledge as I go (the rear tranny should be physically installed in a few weeks).
Cheers,
Mike
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- Posts: 1696
- Joined: Fri Apr 04, 2008 1:28 pm
Re: GM 4T40-E
In general, we don't add transmissions to the supported list, users do.
How it works is that a user (or users) does the homework to see if the trans can be controlled using the current functions incorporated into the MShift code. That requires looking through our documentation here: http://www.msgpio.com/manuals/mshift/index.html and comparing these functions to the transmission's 'needs' (usually from a factory service manual, google, etc.).
Where there is a need for something that isn't in the code, it can usually be added, either by me or the user. For example, this is what we did for the Ford voltage-style shift lever and many other additions to the code.
I don't know specifically about the transverse GM auto transmissions, but I have heard people say they are very similar to the 4L60E - so if that's the case setting one up to run with the current code shouldn't be too hard. Things like shift patterns, gear ratios,VSS teeth, etc., are already user-configurable in the code.
Lance.
Re: GM 4T40-E
Thanks for the feedback, I was hoping that somebody already had a 4T40 transmission in the testing phase.
I have managed to get some info.
Found a wiring diagram for the 4T40
The ratio's for the transmission are:
1st - 2.957:1
2nd - 1.623:1
3rd - 1:00:1
4th - .682:1
Final - 3.91:1
The VSS Teeth count is 30.
I can't locate the exact shift solenoid pattern yet but it appears to match the 4L80 as far as solenoid\valve setup.
Cheers,
Mike