V8 in M37 pros/cons

[M6Scout]

Hi folks I’d like opinions on v8 swap , I will be over the road more than off roading, very hilly here in upstate NY.
I appreciate any input.

Thanks

[PoW]

The ring & pinion in the M37 will not tolerate much more torque and road speed than stock.

I put some 250K on my diesel/overdrive M37, only ruining 13 sets of gears.

Most of the gearsets were NOS complete units back when you could get such.

When I used just gears, synthetic lube, tight or loose setup, nothing made any difference.

PoW

[W_A_Watson_II]

Axles are the weakest link (I've broke MANY), I've only broke one ring gear pinion, and it was due to me abusing it and the ARB Air Locker letting go.. If you up the tire size to 39.5", you can get good speed. I run 3,000 RPM at 60 MPH.

[M6Scout]

Thank you for your reply

[06boblee]

If you pair that V8 with an overdrive trans, it will help a lot. Check with Charles at M series rebuild on the strength of these differentials, they are plenty strong if set up correctly.

[PoW]

People just don't listen. Parts didn't break, they wore out.

The differential (spider) gears never did develop problems; the problem is the ring & pinion just won't hold up in the long run (10K mi/year) turning some 3000 rpm at highway speeds.

As far as setup was concerned, most of those that died on me were complete factory new dropins. If Dodge didn't do a good job, it can't be done.

Then again, if you never will drive it much, it won't matter.

PoW

[sturmtyger380]

The V8 will give you more top end. I would invest in getting disk brakes at least on the front. Charles offers a disk brake kit.

[superbee70]

Upstate NY here also, if you call WNY upstate.

I'm in the middle of a swap/regear. Unless you love driving 45MPH or less, especially on hills, you won't like the straight six standard axle setup for long. I'm swapping a 360 plus front and rear axles from an 89 dodge 3/4 ton. Swapping axles gets you better brakes, better gearing, better choice of rims and tires. Not a difficult swap, you either need to shorten the passenger side front axle or offset the spring 1.5". I'm not looking for great road performance but would like to drive the 30 miles back and forth to work at a reasonable speed.

[Kyjim]

So I'm assuming they don't make any new ring and pinions for these axles? You have to excuse me i just became an owner of one and just trying to find out a lot of info. Thanks!