Manual Transmission Conversion

ShaqDiesel · **Posted:** Sat Aug 08, 2015 11:56 pm

A question for the group:

Has anyone heard of or seen a Liberty converted to a manual transmission? Any links or information you have would be awesome. I grew up driving a stick shift and believe they are the superior option for my style of driving. Cheers!

CRD_Joe · **Posted:** Sun Aug 09, 2015 12:50 am

Ya good luck with that. Youd have to get all the parts from a European truck, including the computer.

ShaqDiesel · **Posted:** Sun Aug 09, 2015 1:40 am

Just a question.

Lancer · **Posted:** Sun Aug 09, 2015 4:25 am

I recall that this was asked a few years ago, and the conclusion was that the sheer amount of work involved - and the cost, meant it just wasn't worth it.

senatorjohn · **Posted:** Sun Aug 09, 2015 5:43 am

Numerous manuals in Australia as another option. Cost of shipping ??.
John

95Z28A4 · **Joined:** Sun Mar 30, 2014 9:53 am **Posts:** 297

I think you must first identify the pieces/parts needed for the conversion. Gathering the parts to convert my 1994 Jeep Grand Cherokee from automatic to manual transmission took a long time. I purchased a very low mileage AX15 from a 1996 Cherokee for the conversion. To install a manual in the Liberty you will probably need the following:

*transmission
*flywheel
*clutch/pressure plate
*clutch hydraulics
*clutch/brake pedals
*transmission mount
*shifter
*shifter inner boot
*shifter outer boot
*front driveshaft
*rear driveshaft
*ECM or ECM reprogram
*possible transfercase input shaft replacement
*rewiring for the clutch pedal engine start permissive and cruise control interlock

I think the only parts that may require importing from across the pond(s) are the flywheel and clutch/pressure plate and possibly the ECM. If you have the part numbers, the DCJ dealer can maybe order those parts new. My local DCJ dealer can't/won't lookup export part numbers, but they have ordered them for me if I have the part number. The hydraulics are available on Rockauto. I believe the rest of the parts can be sourced from a 2002-2007 3.7L Liberty. The 3.7L driveshafts may or may not work, but I believe a driveshaft shop can build/modify the driveshafts.

For a transmission, I would choose the 6 speed NSG-370 (used in the 2005 - 2007 gasoline 3.7L Liberty) over the 5 speed NV3550 (used in the 2002 - 2004 gasoline 3.7L Liberty). I would use the NSG-370 not because of the extra gear, but because of the issues with the NV3550 synchros. I chose the AX15 over the NV3500/NV3550 for my Grand Cherokee conversion for the same reason.

You may find that the CRD 3.73 gears are not manual transmission friendly. Overdrive gear in the NV3550 is .78:1 and in the NSG-370 is .84:1 compared to .67:1 in the 545-RFE.

Other possible transmission candidates are the GETRAG 238 from the 2006 - 2009 Dodge Dakota and the NV3500 from the 2nd generation Dakota. Overdrive gear is .79:1 in the GETRAG 238 and .73:1 for the NV3500.

thermorex · **Posted:** Mon Aug 10, 2015 9:17 am

The main issue with the 6 speed manual transmission is that is way weaker than 545rfe, even weaker than ax15. If anything, you'd want the ax15 or stronger. The 6 speed will severely limit your towing abilities, as I remember similar conversations from some time ago. Plus, other than shifting when you want, why would you really want the manual transmission? I am genuinely asking, as a person that favors manual over automatic. Imo it ain't worth to do this for a crd.

ShaqDiesel · **Posted:** Mon Aug 10, 2015 11:44 am

thermorex wrote:

Plus, other than shifting when you want, why would you really want the manual transmission? I am genuinely asking, as a person that favors manual over automatic. Imo it ain't worth to do this for a crd.

Reasons:

1) Better gas mileage
2) Ability to push start in the case of a dead battery
3) Control over torque, especially when going up hills

papaindigo · **Posted:** Mon Aug 10, 2015 12:05 pm

Hum:
1. doubt the mpg would be any better than what can be achieved with the GDE EcoTune
2. maybe but I'm not sure any fuel would be injected with a totally dead battery
3. doesn't really matter except when towing and a GDE tow tune take care of that.

As I recall the manual dual mass clutch plate has problems.

Bottom line my personal opinion is that you are opening up a several thousand $ time consuming can of worms for no significant gain. Not like in the simpler days of 1965 where engine/transmission swapping was a relative piece of cake.

ShaqDiesel · **Posted:** Mon Aug 10, 2015 2:40 pm

1) The absence of the torque converter should result in slightly better gas mileage.
2) I've been able to push start several vehicles with a dead battery, though they were gassers.
3) It does matter, because I find the vehicle shifting at the wrong times. When climbing a hill or pass, it will often shift into overdrive and lug the engine. It's an easy fix to turn the o/d off, but maybe I just like stick shifts better.

The manual conversion does seem like more trouble than it's worth. I was just trying to stir up conversation on the subject to see if it was feasible.

Sir Sam · **Posted:** Mon Aug 10, 2015 2:46 pm

ShaqDiesel wrote:

2) Ability to push start in the case of a dead battery

This won't happen. These engines crank and crank and crank but wont start when the battery voltage is too low to run the ECU.

Seriously, the engine can still crank fine but not fire because the ECU flatlines before the starter.

I've posted part numbers and information before on how to do the conversion, there are pictures out there of my 5speed setup. Most of the donor parts are available in the US, just gotta hit a junkyard. I think the flywheel and clutch are the only parts you cant buy used here, but can still purchase new with the right part numbers. Again posted before.

papaindigo · **Posted:** Mon Aug 10, 2015 4:04 pm

Shaq - I'm not sure I understand "When climbing a hill or pass, it will often shift into overdrive and lug the engine." Yes the transmission can shift when climbing a hill or pass but not up into overdrive or such that it will "lug" the engine. Rather it will down shift into a lower gear which brings the engine rpms up or way up depending on how far down it shifts. When stoutdog and I came back from Tempe, AZ to Tallahassee (I-10 all the way) in his fully loaded 06 pulling a fully loaded 5X8 uHaul we experienced the down shift but quickly found that this could be avoided (in 5th/overdrive) by simply applying so extra manual throttle before hitting the up slope. Essentially "anticipating" the up slope which cruise control cannot do. The GDE towing tune helps with this a bit but we don't tow enough often enough to matter.

As to the torque converter or automatic eating into mpg that was certainly true back in the day but not so much today. In fact there are a number of vehicles that get better mpg with an automatic than with a manual.

The Scott McLean · **Joined:** Tue Feb 15, 2011 9:19 pm **Posts:** 43

I too would love to see a five or six speed manual. From what I recall, the issue was from the transmission to transfer case attachment point.

Sent from my Nexus 5 using Tapatalk

Sir Sam · **Posted:** Mon Aug 10, 2015 11:48 pm

The Scott McLean wrote:

I too would love to see a five or six speed manual. From what I recall, the issue was from the transmission to transfer case attachment point.

Sent from my Nexus 5 using Tapatalk

the nv242 found in US CRDs will boltup to any ax15 post 1991 or nv3550 or nsg370. This is not an issue.

Billwill · **Posted:** Tue Aug 11, 2015 3:31 am

ShaqDiesel wrote:

thermorex wrote:

Plus, other than shifting when you want, why would you really want the manual transmission? I am genuinely asking, as a person that favors manual over automatic. Imo it ain't worth to do this for a crd.

Reasons:

1) Better gas mileage
2) Ability to push start in the case of a dead battery
3) Control over torque, especially when going up hills

I recently had the problem of a dead battery on my manual 5 speed 2002 Export 2.5 CRD...just as I was about to follow the removal truck from my old home to my new one. Fortunately the removal personnel were able to give me a push-start and I drove straight to a Battery Center and had a new battery fitted.

I like the manual shift but as I get older and my joints start packing up I would probably get an auto shift next time....only problem with the new auto boxes is that they are so complicated with computer controls and are prone to give a lot more problems :shock:

dirtmover · **Posted:** Tue Aug 11, 2015 8:15 am

Sir Sam wrote:

ShaqDiesel wrote:

2) Ability to push start in the case of a dead battery

This won't happen. These engines crank and crank and crank but wont start when the battery voltage is too low to run the ECU.

Seriously, the engine can still crank fine but not fire because the ECU flatlines before the starter.

Yeah but in this case the starter is causing a brownout that results in the ECU failing. If you can crank the engine there is sufficient reserve in the battery to run the ECU properly if the starter was not engaged and pulling the voltage down. Push starting would be feasible with a manual in that situation.

Sir Sam · **Posted:** Tue Aug 11, 2015 9:25 am

dirtmover wrote:

Yeah but in this case the starter is causing a brownout that results in the ECU failing. If you can crank the engine there is sufficient reserve in the battery to run the ECU properly if the starter was not engaged and pulling the voltage down. Push starting would be feasible with a manual in that situation.

Yes, it could be.

I think a small 12V battery next to the cranking battery would work well too on an isolator. Plenty of juice to run the ECU, but on an isolator so the main battery cannot drag it down. Alternator would charge both but the ECU would only run off the second battery.

I would say dual batteries but there just isnt the space under the hood for a full size battery.

Squeeto · **Posted:** Tue Aug 11, 2015 12:43 pm

Sir Sam wrote:

I would say dual batteries but there just isnt the space under the hood for a full size battery.

Super cap mini-pack:
https://www.youtube.com/watch?v=GUXM1XuLUIs

jws84_02 · **Posted:** Tue Aug 11, 2015 12:52 pm

Squeeto wrote:

Sir Sam wrote:

I would say dual batteries but there just isnt the space under the hood for a full size battery.

Super cap mini-pack:
https://www.youtube.com/watch?v=GUXM1XuLUIs

Those are cute lil babies. I've been running the 3000 farads ones for about 2 years

Manual Transmission Conversion

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