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8spd 4l80e VS 6 spd allison??

22K views 16 replies 7 participants last post by  Starvin 
#1 ·
So alot of you know I have been planning on installing a 6spd allison for the past year or so. I like the idea of having as many gears as possible to get great acceleratioin and mileage at cruising speeds.

The allison has good gear ratios and is designed for a diesel application not to mention will handle my twin turbo'd engine with very minor mods. the only problem is I have been waiting on the electronics to control it for over 6 months now and I am getting tired of waiting, not to mention I dont think this bone stock 700r4 is gonna last long with my motor. Oh yeah, I will probably have to severly mod my trans tunnel to fit the allison.

The 4l80/85 is a good trans in my opinion with the proper internals and converter not to mention it already has several options for electronic controls. I can install a pcs controller and have 2 different shift programs and I think it will handle my little motor after a proper build. The downside is that it will be expensive to build the 4l80/85 for ultimate reliability with my motor and get a properly selected converter, I would imagine I could rack up a $5000 bill quickly for a complete setup. I could always do it in stages as money allows though, converter and electronics first then build the internals later on.

As for getting more gears out of the 4l80/85 I have thought of installing a gear vendors behind it. I could have a .59 overdrive for excellent cruising rpms at 70mph for optimal mileage but still have great acceleration, I could even bump up to a 3.55 gear instead of the 3.08 or 3.27 I have now. I have pcs looking into a way to program their computer to make the gear vendor shift automaticly for me instead of having to push the button everytime I want to use it. I have also considered looking for a 4l80/85 from a newer model chevy van with a duramax since they come with that style trans instead of the allison.

Can anyone tell me the difference between the 4l80e and 4l85e?


The gear ratios are

Allison
3.10
1.81
1.41
1.00
0.71
0.67

4l80e
2.48
1.93 (GV o/d)
1.48
1.15 (GV o/d)
1.00
0.78 (GV o/d)
0.75
0.59 (GV o/d)
I would probably never use the gear vendors to spilt gears only to have the extra overdrive gear, I just wanted to show you all the gears possible.


So what do you guys think? Which one?


Either way I wont be doing this for a little bit longer but I hope to have the truck running soon and I know the 700r4 wont last long so I need to get something in the works that will last and I refuse to have my truck down for several months again waiting on trans electronics for the allison. On the flip side if the 4l80 sounds like a bad idea I will wait for the allison.
 
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#2 ·
I would probably go with the built 4l80e with the gear vendors. Allisons trans are not cheap either, they are a good trans but i think that they are over rated, and you might have to build the allison to. (i forget how much power you have) 4l80e can e built to be a decent trans, plus theres less electronics thats my $.02.
 
#3 ·
I think the 4L80E is a good tranny in it's OE applications. Beyond that and what an HD3 transgo kit and adjustable force motor can do for one there isn't much out there for practical upgrades. There are a lot of parts sold as upgrade pieces that are just chinese crap that looks different from a stock piece.

The biggest disappointment I have with 4L80E's is the case. They have got to have the cheeziest, thinnest case/bellhousing casting of any transmission. You can crack a 4L80E case trying to get one off the block dowels!

I have little experience with the newer Allisons besides riding in pumped up Duramax pickups and must say by my seat of pants feel an Allison works better and handles far more than the best 4L80E I could build.

In your favor, you have a really light 2wd truck that's going to be very traction limited. A 4L80E would likely last awhile.

If in your shoes I think I would settle for a 5 speed Allison for the time being and eventually upgrade to the six speed controller if it's ever completed. This route has to be cheaper than a built 4L80E and Gearvendors, it's cleaner and simpler.
 
#4 ·
Dustin, I have thought of the 5 spd allison but it wont give me the gear ratios I want for highway speeds. I want this truck to be a jack of all trades so to speak and be fun around town while pulling down good mileage at 70-75mph on long cruises. (Hot Rod power tour 2010)

I have been reading and calling people and found out that the 4l85 is a little stronger trans. I have also found out from an extremely reputable tranny guru that the 4L85E that comes behind the duramax powered chevy vans has hardened internals and is stronger from the factory than a typical 4l80/85. I wondered about this since they are listed as different from other apps that use gas motors when you call junkyards or GM.

I called a local yard (the only one so far but not the last) and they quoted me $1200 for a complete 4l85e trans with converter from a 2006 chevy 2500 diesel powered van with 48,000 miles. I think this sounds a little steep and if I look around I may find a cheaper one but then again this would probably be the best application to get a 4l80/85 from since it appears to be the strongest factory version and will probably get me by for a while. I may be able find it cheaper with some searching but to my knowledge they dont make many diesel powered vans so I may have to suck it up if I choose to go that route.

On a side note, the guys at gear vendors said they dont recomend running the gear vendors with the 4l80e and a 4 cylinder diesel. They say the harmonics from a 4 cylinder diesel ( they say only the 4 cylinder diesel for some stupid reason) kills 4th overdrive when using the gear vendor overdrive with it. I dont understand this/??? after further discussion he said most apps he has seen this happen in were original apps (ie 10-13,000 trucks) I think it would be fine in my under 4,000 pound truck. I can see full throttle with a .59 trans gear not being too happy pulling steep grades and alot of weight. What do guys think?
 
#5 ·
#6 ·
Not a member there so I cant read it. I have talked to a couple people that have 6spd allisons and they were done by either destroked or brayden fleece. The only problem is getting them to make some more, namely for me LOL. The more I look into it the more I like the idea of the 4l85e from a duramax powered van with the gear vendors overdrive but its still all up in the air.
 
#7 ·
I talked to powertrain control solution today and they said their controller can operate the gear vendors overdrive. From what I understand the pcs controller will operate up to 6 gears total so you can run a 4 spd auto and activate the gear vendor overdrive on top of any gear up to 2 times. Basicly you can have 1st, 1st o/d, 2nd, 3rd, 4th, 4th o/d or any other combo you want for a total of 6 gears. you can also jut make it a 5 spd if you want or not use the gear vendor and keep it a regular old 4 spd. Once you set it up like a 4,5, or 6 spd with the gear vendors overdrive you can program it like any other factory type auto 4,5 or 6 spd by choosing rpm, tps, etc to select how and when it shifts.

After looking at it on paper I would say the best ratios would be.

1st 2.48
2nd 1.93 (GV o/d)
3rd 1.48
4th 1.00
5th 0.75
6th 0.59 (GV o/d)


This would give a pretty close ratio trans with a great cruising gear at highway speeds and may be a benefit or not, I gues a real world test would be needed to see how it performs but on paper it sounds nice to me.

The biggest problem I see to this is cost. The 6spd allison can be had with low mileage (under 50K) for $1k-$1,500, then add roughly $1600 for the controller when you can get one, under $50 to shorten driveshaft for a total of $3150 for a stock trans that will need a converter and transgo jr, for about an extra $1800 roughly, total cost $4950.

6spd 4l80e from a 06-07 chevy express van with hardened insides roughly $1200 with low mileage, controller $850, driveshaft mods $50, used gear vendor o/d $1500 on the high side. toss in a custom converter $?? (dont know what a 4l80e converter cost) $1000 estimate, new alto clutches and steels with a transgo shift kit, $500. Total cost $5100

I guess cost wise it is a wash, with the exception tha I can get the 4l80 installed and built up to handle the abuse for around $3500 then buy the gear vendor later on to ease the wallet pains.
 
#8 ·
Trying to control the 6 speed

I ran into the exact same thing with gear vendors and PCS for the 4L80E. All exactly as you describe – 4 cylinder issue and so on as well. Also, my math jive's with yours. The Ally 6 speed may be done for cheaper depending on the tranny costs and upgrades for both. I like the gearing options for the Allison – I can keep my stock rubber and rear end and cruise great at 65-70.

I am currently waiting on the 6 speed controller and/or also investigating how to control it if I can get the Allison DOC 8.0 program. I've been looking through the inputs/outputs etc. of what is required and what can be done and if its possible to do it myself. I have wiring diagrams as well. Have had some but not much help from Ally dealers, Fleece, Destroked. I'll keep trying and will post my progress on the issue. I plan on talking to Brayden some more. I'll have to check the link to the other forum and check on the info there.

Currently, I have a 2008 Allison 6 speed in my garage just waiting. Got it from the local dealer when a few trucks came in damaged and they parted them out! Only 78 miles and basically new.

This isn't saying I'm on hold, just starting my build and am fabricating the dash for gauges etc this weekend hopefully.

So has anyone else actually swapped in an Allison 6 speed standalone yet? Or is it just the 5 speeds I’ve heard about?

Marvin
 
#9 ·
I am confident noone on this site has swapped a 6 spd yet but it has been done by a few around the country but not many maybe 3. I would love to hear any progress you make on this setup but I am starting to lean more towards the 4l80 and gv. I like the ratios better and selectability, not to mention the alli is huge and would almost certainly require trans tunnel mods. GM raises the silverados a couple inches from the factory to clear the allison and others that have swapped the A1000 into tahoes and subs with a duramax have had to install 3" body lifts just to clear the allison. The 4l80/GV can just bolt right in with just a new crossmember (which I want to redo anyway to go above the exhaust) and a shorter driveshaft.
 
#10 ·
the duramaxes in the vans have a derated program in them compared to the pickup trucks. strickty because the GM trans 80 or 85 can't take what the duramax can give. and the allison just won't fit in the vans. so they had no choice but to derate the engines.


go with an allison is just a better transmission. any planetary style auto is better than your automotive style clutch pack automatic.



heres some food for thought...................




 
#12 ·
Thanks, I already have the 1000 manual its a good read. Those pics look familiar, kinda like when I tore my old stocker apart before I installed the ATS extreme.

I am still leaning towards the 4l80e/GV setup for the better gear ratios though.
 
#13 ·
Thanks, I already have manuals as well and are quite informative. As mentioned, i have a 2008 Allison 1000 waiting to mate to the mechanical cummins - both in my garage. If you have any information regarding controlling the allison as a standalone, that would be great. I believe if I have the Allison DOC programming tool, I would be able to enable/disable the inputs/outputs of the controller, etc. The problem is having Allison supply you with the reprogramming capabilities. In order for them to allow this, I need to show proof/certificates of training, etc. Thanks for any help.
Marvin
 
#14 ·
Marvin, good luck with getting allison to help you on programming the a1000. I tried for 6 months with no luck. I hope you have better luck with it though, please let me know if you find anything.
 
#15 · (Edited)
While at the Mid America Trucking show a few months ago in Louisville I stopped at the Allison booth..

Spent a good while talking to Don Bixler, the VP of sales for Clarke Power Services, inc. in Decatur, IN, an Allison dealer
Most of my questions were about adapting an Allison 2000 or 3000 to a mechanical engine, my Detroit 4-53T.

Here's what I learned, and what he recommended:
1, Find a good used transmission, and pull everything related to it, particularly the wiring harness and computer.
2, Torque converter should work in most cases, but if I want the best match for my engine they can help me pick the right one.
3, The only external signal needed is a TPS sensor, and Allison makes or offers a very nice one.
4, They will sell a "blank" controller, or better yet can clear a used one. Then program or reprogram it to suit a mechanical engine.
5, They can make a 5 speed into a 6 speed, but it's not recommended for the older ones. I forget what year or after I should be looking for? Some of the medium duty versions may be 5 speeds from new while 6 was an option, they can give you that option back.
6, Allison did offer 2000 and 3000 series transmissions behind Mechanical Cummins engines, so this whole mechanical engine swap stuff is not new to them...
7, Theoretically a 2,000 or 3,000 should bolt on torque converter and all where an older mechanical Allison was, as an example he said a AT545 can be swapped for a 3000 with the same size SAE housing. However after asking around one friend had to make an adepter to swap a 3000 where a MT653 was... Don't have a straight answer yet, but it's supposed to be pretty simple to bolt up with factory parts.

Don seemed willing to help me swap a 3000 behind my 4-53T if I ever want to, and explained that it's not that difficult.
What I don't know is if he will follow through with his offer of help, and what the reprogramming and advice will cost me?

If you want give him a call (260) 639-3750, and remind him of our conversation at the show in Louisville about an electronic Allison behind a 4-53T in a 48 Chevy truck. Explain that you're not Grigg, but that I suggested you call and ask about your project.

Please let us how if he is any help, and at what cost.

I've found the hardware I need to swap an Allison if I want to, now all I need to do is stumble onto a 3000 series at a good price.

Grigg
 
#16 ·
Thanks for the info Grigg, I will give him a call tomorrow if I remember, I am very tied up with this pump right now.
 
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