Exciter Ring for Allison 6spd

[Jackflash]

Hey guys Im new to the forum , and I am eagerly awaiting my LMM and 6spd Allison to arrive for a retrofit.

Basically the setup I am running is as above in front of a Atlas 4spd Transfer Case.

The question I have is that if I use the Atlas and don't opt for the VSS to be added, can I add an 'Exciter Ring' to the tail housing of the Allison on the output shaft like in a 2WD?

Can anyone help in the setup and advice on where to locate an Exciter ring for my setup.
Correct me if Im wrong but I am pretty sure it needs to be 40 tooth item for the TCM!!???
Cheers

 

[MaxPF]

Is this a complete swap, or are you putting an Atlas in a GM DMax pickup? The reason I ask is that, in the former case, you are on the right track. Go here to see how another guy did it and the part # of a reluctor he used. The only reason you would need the VSS in the Atlas tailhousing would be to have an electronic speedo drive that is accurate in any of the t-case's low ranges. If electronic speedo accuracy in 1:1 range is all you are concerned with, tap into the replicated TOSS output from the TCM. Also, you will either need to not use the 4-lo ECM input, or set the low range ratio in the TCM to 1:1.

If you are putting the Atlas in a GM pickup, then you also have the TCSS (traction control system) to worry about, which is a whole 'nother can of worms.

There is another option for a TOSS, but it's..... complicated. And, I'm not sure you want to drill a big hole in your Atlas

 

[Jackflash]

Yes it is a complete swap. I have retained all of the harness and components to make the retrofit easier to achieve.

The receiving truck is a 2007 Nissan Patrol, coincidentally about the same gross weight as the 4x4 Silverado LT.

I should inform that the Atlas is the 4Spd and as a consequence I dont think I can use the 'Lo range' input at the TCM or other.

What is a little concerning is the TOSS you are refering to. Is this feature something that can be switched off as the driver wants or is it a 'non input' type traction control?

Thanx for your expertise on the matters.

 

[MaxPF]

Yes it is a complete swap. I have retained all of the harness and components to make the retrofit easier to achieve.

The receiving truck is a 2007 Nissan Patrol, coincidentally about the same gross weight as the 4x4 Silverado LT.

Cool

I should inform that the Atlas is the 4Spd and as a consequence I dont think I can use the 'Lo range' input at the TCM or other.

Actually, you can. Since you will be putting your TOSS on the output of the trans, you would just need to use EFI Live or HP Tuners and set your low range ratio in the TCM to 1:1. 4-Lo is nice because it gives you a separate shift schedule that is more suitable for use in low range. Most likely you will only use it in your highest low range, and you will end up using tap shift or manual 1 in the 2 lowest ranges.

Remember that whether you use the low range shift scheduling or the normal shift scheduling, your shifts will happen at progressively lower speeds as you shift into lower ranges on the t-case. This is a consequence of having your TOSS on the trans output rather than the t-case output.

What is a little concerning is the TOSS you are refering to. Is this feature something that can be switched off as the driver wants or is it a 'non input' type traction control?

TOSS is the Transmission Output Speed Sensor. TCSS is the Traction Control System. Unless you are swapping in the TCSS module along with the ABS hydraulic module and all the other stuff needed for the TCSS to work you don't need to worry about it. If you are swapping that stuff in, then I can't help you since I have never messed with it

 

[Jackflash]

ok so all I need to do is access the data on EFI live and adjust accordingly for the 4-Lo ratio.

Im not sure if the LT came with TCSS or even if it was included, but as I specified 'all' electrics, I am assuming it is there.

The identification process should be easy enough as I asked for all terminals (plugs) to be labelled so when it arrives I will let you know thanx Max.

 

[duratothemax]

Cool



Actually, you can. Since you will be putting your TOSS on the output of the trans, you would just need to use EFI Live or HP Tuners and set your low range ratio in the TCM to 1:1. 4-Lo is nice because it gives you a separate shift schedule that is more suitable for use in low range. Most likely you will only use it in your highest low range, and you will end up using tap shift or manual 1 in the 2 lowest ranges.

Remember that whether you use the low range shift scheduling or the normal shift scheduling, your shifts will happen at progressively lower speeds as you shift into lower ranges on the t-case. This is a consequence of having your TOSS on the trans output rather than the t-case output.



TOSS is the Transmission Output Speed Sensor. TCSS is the Traction Control System. Unless you are swapping in the TCSS module along with the ABS hydraulic module and all the other stuff needed for the TCSS to work you don't need to worry about it. If you are swapping that stuff in, then I can't help you since I have never messed with it

why are you confusing this thread with stuff about traction control? Totally irrelevant. Stabilitrak (also called ESC or VSES...ive never heard it referred to as "TCSS", whats the extra "S" stand for??) wasnt available in the HD's until 2009, and even then, it only came on short bed trucks. It wasnt until 2011 that it was made standard on all single rear wheel trucks.

And also. You're forgetting that If you dont setup the low range input and speed sensor properly, the trans will fail the 1-2 shift and you'll never even past first gear. The only way you'll be able to do it is put the speed sensor PRE-transfer case...because the TCM isnt setup for 4 different low-ranges.

The output speed sensor isnt "just for the speedometer"

 

[MaxPF]

why are you confusing this thread with stuff about traction control? Totally irrelevant. Stabilitrak (also called ESC or VSES...ive never heard it referred to as "TCSS", whats the extra "S" stand for??) wasnt available in the HD's until 2009, and even then, it only came on short bed trucks. It wasnt until 2011 that it was made standard on all single rear wheel trucks.

I thought traction control was part of the ABS setup as early as 07 Thanks for the clarification - I'm too used to non-HD vehicles which all have that crap Anyway, like I said, it was an "if" he was putting an Atlas in a GM pickup. Since he's doing a swap it is irrelevant... unless the Nissan ABS systems need a speed input from the t-case.

And also. You're forgetting that If you dont setup the low range input and speed sensor properly, the trans will fail the 1-2 shift and you'll never even past first gear. The only way you'll be able to do it is put the speed sensor PRE-transfer case...because the TCM isnt setup for 4 different low-ranges.

The output speed sensor isnt "just for the speedometer"

I forgot no such thing. I told him in my first reply that he was on the right track putting a TOSS on the trans output. I said the VSS on the output of the Atlas would only be needed if he wanted to have his speedo accurate in any low range (it would only drive the speedo, NOT the TCM). Otherwise he can use the replicated TOSS output to drive the speedo, but it will read high by a multiple of whatever low range ratio the t-case is in.

 

[DMAX403]

How come you don't just use the standard Nissan transfer case, its ple

nty strong enough.

 

[Jackflash]

How come you don't just use the standard Nissan transfer case, its plenty strong enough.

It was never a question of strength, I happen to believe the Nissan transfer case is super tough but....
Based on the current low range gearing I have (3.8:1) I have found out that sometimes this is just too low for moderate off-roading (sand mud you know what I mean).
However I am not prepared to go back to standard 2.00:1 lo-range, because I tow an off road camper through some rugged places; and very often I will need the extra engine braking on steep descents. (3.8:1)

The Atlas is also manufactured to bolt straight onto an Allison with a 4x4 housing, also it has 3 different Lo-Range options which for me was one gear better than perfect!! 2.00:1 , 2.72:1, 5.44:1 + 1:1 High range
And my favorite feature on the Atlas is that you CAN use LO-RANGE in either front wheel drive or rear wheel drive or both!!!
How good is that:woott:
Hey by the way NICE TRUCK !! Gotta hand it to Heath he does a great conversion.

Cheers Jay
Yeah its me Jay from the Patrol Forum lol surprise!!

 

[MaxPF]

That's the same reason I am going to run a 203-205. Most off-roading can be done in 1:1 or 2:1, but if I need to climb a waterfall or navigate a rock garden I will have 4:1 for low speed crawling.

The only thing with that low of gearing is you have to be careful - it puts your driveshafts and axles under a lot of load if you get bound up and try to throttle your way out. Even guys with relatively tame gas motors can break shit at will with this kind of gearing

 

[Jackflash]

yeah your absolutely correct, I have had mine for the last two trucks, and I gotta say it doesnt take much to start breaking things in the driveline....