5 speed trans alternative to Marks ?

[Wylder1324]

So I have been trying to decide what the next step is with my Patrol. He has been a little neglected in the restoration process in favor of my 65, 75, and 85 Datsun trucks but it is his turn again. Obviously driving these guys on the open road is a challenge as they come from the assembly line….I have been trying to decide what I want to do about that. I have had some thoughts of V8 power….if I went that route I would however be looking at the Nissan VH45 as I am pretty adamant about keeping these as Nissan as possible. This is something my Datto/Nissan junky mechanic have actually been really researching up on.

My other option is finding a transmission setup that will work with the current straight 6 setup…..the Marks seems to be unobtanium short of getting lucky…..am I wrong ? Even so, what kind of highway speeds is it capable of with this set-up ? I am not looking for a race car but 55-60mph is pegged out at the moment and I would def like to achieve a comfortable 70 without feeling like I am redlining the RPMs the entire time. Is there an alternative to the Marks ?

[RiverPatrol]

Welcome to 60Patrol!

Here is an excellent thread about a Patrol in Australia with a Marks in it, and what it can accomplish with the Marks: http://www.60patrol.com/forum/viewtopic.php?f=20&t=2213

Other than that, I am not aware of any other trans that will drop into the Patrol. I have a Patrol pickup that has a 4 speed in it, built by Marks Adapters as well. Fourth gear is still 1 to 1 though.

[moore_rb]

The problem with an "alternative" manual transmission isn't bolting it to the bellhousing, or finding a clutch disk with the corresponding spline count.

The challenges all begin at the other end, when you realize that no one (except Mark's) makes a transmission with an output shaft that fits the input to the Patrol's transfer case. This leaves you with either:

a) spending a mint having a custom output/input adaptor made.

or

b) replacing the Transfer case as well.

The Patrol transfer case has both the front and rear output yokes offset to the passenger side, so the only compatible junkyard transfer cases out there are going to be the spicer18, Spicer/Dana 20, or a slightly modified NP205 (you can rebuild a 205 to use an extra forward offset gear on the rear output, and move the rear output over to the right)

I did mass amounts of research on this topic when I was first thinking about what I wanted to do with my Patrol(s) and Norville has also done considerable research on this topic as well... perhaps he will have additional information (or other options) that I have not covered here.

[Swerve]

PM sent,

[mundy]

If going engine conversion route can use landcruiser gearbox and transfer as they are offset to correct side.
Or you can buy a adapter for what ever engine and gearbox you like to a rover lt230 transfer case.

I would be really interested if you find anything that will bolt to the original p engine

[Esteban]

If going engine conversion route can use landcruiser gearbox and transfer as they are offset to correct side.
Or you can buy a adapter for what ever engine and gearbox you like to a rover lt230 transfer case.

Very interesting the second route, although it might prove expensive. Another issue will be the length for the SWB Patrols, since the LT230 trasfer case seems to be much longer. I found this link that might be an interesting read in this regard:

http://www.expeditionlandrover.info/lonn_V8.htm

[norville]

Jeep Quatra track TC cases are also offset front rear.

Another route to take may be to swap the rear axle to a narrow track center pumpkin from a full size jeep or early CJ. The you will have more options for transfer cases..

I'm sure of you pick out a tranny and Transfer case that work together the engine adapter can be made. The big hurtle would be input shafts from trans to TC if they are a mismatch. I've seen buys with a mill make an sunbeam alpine engine bolt up to a ford/mazda 5 speed.

I agree for modern day driving more gears are needed, although I'd be happy enough with 4speed.. I don;t plan to cross country drive the thing but I have lots of hills 3 sppeds make life miserable.

bob

[RMP&O]

Land Cruiser H55 5spd and FJ60 split case is the best route to go in my opinion. You get a pretty compact and strong 5spd and a fully gear driven t-case that is also strong and compact. Off-set to the RHS too.

As Rob said, the issue is not in the clutch. Just about any flywheel can be drilled to suit any clutch, size depending of course. Issue is not even with bolting something to the engine. Although that will require a custom made adapter. The main issue is length of the input shaft on the trans. If you go all the way back to the block on the P engine it is pretty doable. Nothing in my opinion is going to work with the Patrol bellhousing. So you go back to the block, build a custom adapter and use the bell housing from the Land Cruiser. The adapter is simply a plate and or big piece of steel that bolts to the block then has the pattern of the bell housing you are using on the other side. Trick here is input shaft length as the flywheel is not going to change. Although I suppose you could change the flywheel too but I would want to keep the Patrol flywheel. Horror stories from high school shop class of a flywheel coming through the floor into your feet is why I wouldn't want to mess with a flywheel besides drilling for a new clutch. One of the reasons the input shaft matters so much is because the spigot bushing is located in the back of the crank. On some other vehicles the flywheel has the spigot bushing and it is not even a bushing but a bearing.

Any ways, I think those are the big issues. My buddy in Colombia fit a 5spd & t-case from a Y60 Patrol to his P engine. A custom adapter is all it took. This is in a MWB though and his rear driveline is very short. So room length wise is also a major issue, especially in a SWB. Somewhere on my computer I have pics of the engine adapter made to fit the Y60 5spd to the P engine.

While I love the P engine and feel it is a great motor, best route to me to get a 5spd is to simply change out the motor along with the trans & t-case. Many Nissan inline-4's and 6's will fit in the engine bay nicely, including turbo diesels which came with a 5spd behind them.

Cheers

[Wylder1324]

I have actually considered several options with a Nissan/Datsun specialty mechanic friend of mine…..I am going to really try and exercise every option to stay with the P and be happy but the jury is still out. One thought was to go with a bored over L28 to 3.0 liters and another was to go with a VH45 4.5 liter V8. Very early in the theoretics…..whatever I do….it will remain Nissan.

[limited slip]

Being in yank land makes your options very limited. But at some point just about every model of engine/gearbox that nissan made was modular and could be swapped about with the right combination of belhousings........

Vh45 sounds great, and it shares the same bellhousing pattern as the tb and td 42 nissan motors. Now that bellhousing apparently will bolt to the front of the 5 speed gearbox found in the 160/mq/mk series of nissan patrols- im 90 percent certain of this being the case on those boxes with the sd33t in front of them. The sd33 na and the l28 both had a shorter input shaft, smaller clutch and bell housing.

F5w81A? Might be the box model number but without consulting my notes im only giving you an educated guess.

Being a v8 you will find issues with the engine fouling on the footwells of tha g60- the engine bay in them is really suited to strait 4 and 6cyl motors. All however is not lost. For best fit of the v8 youreally want to be shifting it forwards in the engine bay by about 4-6 inches- this extra space should give you room to fit your divorced transfer case- either an lt230 or a t100 nissan case which even you yanks can find in old datsun 720 pickups. A simple short drive shaft from the vh45s matching gearbox to the tranny should sort it, plus obviously the new cross members/mounts for engine/tranny/transfer case.
if you do fit the auto from the vh45,it should overcome any shortcomings in low range gearing if you use the t100 transfer case.......

i hope that all came accross coherently.......