Take the 2-minute tour ×
Motor Vehicle Maintenance & Repair Stack Exchange is a question and answer site for mechanics and DIY enthusiast owners of cars, trucks, and motorcycles. It's 100% free, no registration required.

I am the sad, proud owner of a Nissan SD33T (Diesel), mated to a 4 speed T-19. The power this engine outputs (101HP, 160#/TQ stock) means it struggles on the highway, and I don't want to sacrifice my gear ratio to allow for higher top speed. I'd really like to find a used ZF5 or ZF6 transmission for use on this engine, but am not sure what conversion would involve.

Is it simply a flat plate with the correct bolt pattern? I have access to a CNC mill and a waterjet. I'd like to find out what I would need to make this work.

share|improve this question
add comment

2 Answers 2

up vote 2 down vote accepted

A plate between the flywheel housing on the engine and the bell housing of the gearbox would almost certainly be required to mount the gearbox. This would be no problem to produce with a CNC machine.

The problems that then arise would be to reconcile the differances in the two gearboxes.

Will the gearbox obstruct the clutch assembly in any way? Will the gearbox imput shaft engage in the clutch? Will the splines of the imput shaft mate and be driven by the clutch? Will the clutch release mechanism operate the clutch successfully? Will the gearshift lever enter the cab? Will the gear shift lever be obstructed in anyway when shifting gear? Will the gearbox casing fit in the transmission tunnel? Will the gearbox effect the underbody position of things like the exhaust system or fuel tank? Will the gearbox cross member accept the new gearbox mountings? Will the propshaft alignment be in alignment? Will the propshaft connect to the gearbox and allow a sliding joint? Will the propshaft length now be too long or too short to connect to the differencial?

When your vehicle was first built it was with its present configuration. You would need to reconcile each every difference from that first build. In time and expense terms it would be highly unlikely to be a viable undertaking.

share|improve this answer
1  
Also to consider is if you need a new flywheel to match the clutch to the trans, what type of starter will fit the new bellhousing and fit in the chassis. None of these are insurmountable but must be configured into the initial design. –  mikes Dec 22 '13 at 21:23
add comment

There is a company on the web called Phoenix Casting & Machine. They make adapter plates to mate automotive transmissions to non-automotive engines (they also make the spacers for the flywheel to compensate). The SD33T was originally designed as a fork lift engine. If I read the specs right, it has an SAE #3 transmission mount bolt pattern. This is why you won't find many trannies which will mate directly to it.

I have two suggestions for you:

  • Don't reinvent the wheel. Unless cost is a factor, something already exists to mate your engine to a different tranny, so why try to machine something up your self. Phoenix has what you need and can get it to you a lot faster than you can re-engineer something to fit in. Can you create something using a Flojet? Yes, but why would you want to?
  • Consider putting a different engine/tranny combo into your vehicle. Depending on what you might choose, this may actually be a cheaper option, especially considering the area of the States you are located.

Hope this helps.

EDIT: I also found this thread on a forum called International Full Size Jeep Association. It may be of assistance in your efforts.

share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.