1991 Power Ram 50 3.0V6 4x4 engine replacement options. Please Help

[Traz20]

I'm new here but I just bought a 91 Power Ram 50 4x4 3.0 V6 with a automatic 4 speed. The engine runs pretty rough and the overdrive doesn't work. I am looking to either rebuild or replace the engine here shortly but I don't know what matches up to the transmission for a replacement engine. What do you all suggest for a rebuild kit or a engine swap? I want to keep the transmission because I will need the 4x4 in the winter. Also how can I fix the overdrive?

Thanks in advance for any input.

[Traz20]

Is no one on this site anymore?

[pennyman1]

long holiday weekend - be patient, the V6 guys will respond.

[Jeff V.]

These trucks weren't all that popular to begin with, and it seems like most of them are 4cyl and/or 2WD. V6 4x4s are a minority within a minority.

Late 1st gen (88-91) Montero or another 90-95 Mighty Max / Ram 50 V6 is the only thing that drops in with no mods. You might be able to use an early 2nd gen Montero engine (92-95 I think?) but I don't know if it's 100% drop in. There may have been some subtle changes.

Look for posts by ChargerX3. He put a 2006+ Eclipse 3.8L in his truck. Took some fab work, but nothing too serious.

I'm going less ambitious with mine. I've got a 1999 3.5L 6G74 out of a Montero Sport. It's not quite as complicated as Charger's swap, but it's not drop-in either.

I don't know a hell of a lot about the auto trannies, but I think it's a common Aisin or Chrysler unit. Look at the metal tag on the firewall. On the left it'll say Engine 6G72 and under that it should say Transxaxle with another code. What's that code? That'll tell you what transmission you have.

Chrysler and Mitsu used the 12V engines in a lot of cars, so even though the car engine blocks don't bolt right into the trucks, the rest of the parts are dirt cheap. If you're on a budget, or don't care about swapping in a more powerful engine, just rebuild what you have.

[Traz20]

That helps alot, I was just curious it needs work runs like crap, shakes until it warms up and then it still doesn't run well. Does has 204k miles on it and appears to be leaking oil around the heads. Hear of anyone swapping a dakota, ranger, or S10 engine in? I can find those no problem mine appears to be a rare breed haha

[Jeff V.]

I've never seen one of these engines that didn't leak around the heads. Cars, trucks, the Chrysler versions....they all do it. I think it's just some design flaw. They're pretty stout engines otherwise.

I'd cover the basics first. New plugs, wires, distributor cap and rotor. Pull the plastic covers off and check the cam timing. Make sure the timing belt didn't jump. My truck was also hard to start and didn't run well, but a new fuel pump and filter fixed it right up. It starts and runs really well now.

Could be some issues with the mass air sensor or the ECU, but those are less likely. You can't really begin to troubleshoot that stuff until you know the engine is mechanically solid to begin with.

As far as an engine swap, I've never heard of anyone doing one of those engines. I honestly wouldn't waste the effort for anything less than a Chevy V8 if that's the route I wanted to go. I'm only doing the 3.5L because it's mostly a bolt in swap. Custom motor mounts and a wiring harness and I'm good to go.

[Traz20]

I thought about swapping a chevy 5.3 but I want to keep the 4x4, don't think it would match up but please correct me if I'm wrong

[geezer101]

You won't be able to mate the 5.3 to the Mitsu transmission an even if you did, it won't like it for very long (kaboom). This is one of those swaps where I think you'd find it easier to drop the MM/PR50 cab onto another frame that already is set up for cubes+4x4. The V6 rocker cover gaskets aren't a big deal but buy decent seals and use VTR silicon to fend off leaks (my money is on cheap gaskets not sealing properly, the rocker bolts working loose or the original gaskets shrinking from age).

[Traz20]

I might have found a parts truck but it's a 88 4cyl 4x4 auto. So probably won't do me any good. I was hopeing it would at least be the same transmission but looks my my drivetrain came out in the 90s.

I was thinking for swapping both engine and trans when I was thinking of the 5.3 but transfer case is backwards from where I need it so that's a no go.

What engine/trans swaps are the most common for these little trucks? I don't have alot of mitsubishis around here in Nebraska panhandle.

Any info on the overdrive not working on the transmission?

[Jeff V.]

Get the model number of the transmission from the firewall plaque. We might be able to help with that. If it's a common Chrysler trans, that might open up some engine swap options.

[Traz20]

I will check that out tomorrow and post it. Working lots of overtime at work right now sorry for the delay

[Traz20]

Engine 6G72
Transaxle V44C1 4222

[Jeff V.]

That helps. I've got the 1990 factory service manuals for the Ram 50. Hopefully that includes transmission info. I'll check into it this weekend.

FYI, the 4.222 gears are the same as the manual transmission V6s. So that opens up some good options for a rear LSD if you don't already have one.

[Traz20]

Thanks that would be helpful keep me posted. I'm thinking about buying a Haynes manual for it but I'd have to special order it and I'm not sure if it will have everything I need for it.

[Traz20]

See if I uploaded this right. Looking up parts gave me a bunch of options that didn't match the plate can you help me out by telling me which one I have?

[Jeff V.]

I'm not seeing anything uploaded, so maybe you can try again?

Your trans is a V4AC1 (not V44). Which is a Chrysler A500. There's tons of info out there for them.


The A500 and A518 transmissions are found in the Dakota pickup trucks, Ramchargers, Vans and Ram 50 vehicles. In the Ram 50, the transmission is referred to as the R4AC1 for 2WD versions and the V4AC1 for 4WD applications

I uploaded an ATSG service manual for the A500 and A518. Maybe one of the admins can transfer it to the service manual section of the board.

18994

Don't waste your money on a Haynes book. They're ok, but no substitute for the factory service manuals.

Get these for $15. Free shipping :) http://www.ebay.com/itm/1990-Ram-50-Service-Manual-Set-/361961864999?hash=item54469bbf27:m:mTBT4EYCxi1V4HR L7kH13Dg&vxp=mtr

I have those same books, and there's a very detailed section on the auto trans, including a troubleshooting tree for inoperative overdrive.

[Chargerx3]

Jeff knows his stuff. It's been a while since I dove into the auto trans on the V6 but it had potential. It's a derivative of the 727 which can be built to be bulletproof. You also get the advantage of overdrive with your later version. Great combo to put a stronger V6 behind.

[pennyman1]

The A500 is a 904 / 999 with o/d, the 518 is a 727 with o/d. I have never heard of an A518 in a Ram50 / MMM truck - maybe in a Montero with the 3.5 / 3.8 motors.