Rear axle question

[1989k2500]

37” tire and 4.10 gears isn’t too bad, so long as your engine is in decent shape. Your talking 2400-2500 rpm at 65mph. I have 35” tires and 4.56 gears with a 4 speed manual (no overdrive) in one of my trucks. It is spinning nearly 2900 at 65mph which is screaming, but liveable within reason. If you spend much time off road you will appreciate the lower gear ratio since the 3 speed doesn’t have a deep 1st gear.

My truck will mostly drive up to 55mph max. Maybe some time down the road I’ll get a NV4500.
I have only 3 gears , but also have a granny gear.

 

[JWOK]

My truck will mostly drive up to 55mph max. Maybe some time down the road I’ll get a NV4500.
I have only 3 gears , but also have a granny gear.

I misunderstood. I thought you were talking about one of the old 3 speeds (that is what assuming gets you). I was curious how you would have hooked that up. You must have the SM465 like I do. Great transmission for off road.

 

[1989k2500]

Yes sir I got a sm465

 

[454cid]

I am going to get a set of HMMWV wheels. They are 37x12.5 16.5” that’s equivalent to an 85” tall tire

What?

 

[1989k2500]

What?

A 37x12.5 16.5” tire is equivalent to about a 315/85/16.5” tire

You must be registered for see images attach

 

[Schurkey]

Is this a 6-lug truck? What do you plan to do in front? Install different hubs/steering knuckle/calipers/rotors?

Is the brake master cylinder/booster compatible with the bigger brakes?

You'll have to swap the front axle to match the gear ratio of the rear, and then run front tires the same as the rears, or you're playing games with tire size to keep the front and rear tire rotation-per-mile about the same despite different gearing. I'm told that 3% or less difference in rotation-per-mile is acceptable. Might depend on your ABS system, and how sensitive it is.

Sounds like a heap of work just to install military-cast-off wheels with crazy tires.

They are 37x12.5 16.5” that’s equivalent to an 85” tall tire

Obviously not. An 85" tall tire would be seven feet high. 85 aspect ratio I could believe.

 

[454cid]

A 37x12.5 16.5” tire is equivalent to about a 315/85/16.5” tire

You must be registered for see images attach

Oh, ok.... that's a lot different than an 85 inch tire, like you first posted.

 

[1989k2500]

Is this a 6-lug truck? What do you plan to do in front? Install different hubs/steering knuckle/calipers/rotors?

Is the brake master cylinder/booster compatible with the bigger brakes?

You'll have to swap the front axle to match the gear ratio of the rear, and then run front tires the same as the rears, or you're playing games with tire size to keep the front and rear tire rotation-per-mile about the same despite different gearing. I'm told that 3% or less difference in rotation-per-mile is acceptable. Might depend on your ABS system, and how sensitive it is.

Sounds like a heap of work just to install military-cast-off wheels with crazy tires.


Obviously not. An 85" tall tire would be seven feet high. 85 aspect ratio I could believe.

I am swapping everything over. I have all the parts I need available. The entire front end will move over.
With it, the rear axle will be swapped.

Last week I’ve swapped the engine and with it every wiring harness, relay, computer and dash . I love the 454

 

[1989k2500]

Oh, ok.... that's a lot different than an 85 inch tire, like you first posted.

Yes that was a typo in the first post