Excuse my ignorance!

[R.E.D]

I know this has been thrown around plenty ...but where exactly is the tag in the axle that contains the gear ratio..im swapping my rear diff for one that has been factory drilled and tapped for the transverse torque rod bracket and I would like to be able to check the ratio in the axle that I plan to buy in order to match it to the ratio in the front diff....

Im doing this cuz it would be easier and cheaper to go to the scrap yard and swap the owner my working diff for one his ..just would have to pay a lil difference in price but definitely cheaper than drilling and tapping...

Also since im just swapping the diff itself and not the whole axle , would this be a direct drop in fitment or the axle and diff have changed over the years?.would I have to buy a corresponding 1996 model diff since that's the year model of the truck?

Please advice

RED

Ps:Picture is off the web and not the exact diff I would be buying.

[j hancock]

It is stamped where it says auto lock Mack in your picture. There is a machine pad where it will say the ratio. It actually is a little below the yellow marker.

[R.E.D]

great thanks I will check it out!

[R.E.D]

I checked the location and it seems like I have 4.17 rears...are these considered high or low? Could I swap them for ones that are a lil bit more dirt friendly...truck is 96 rd688s. T2090

[j hancock]

You could go with 4.64's. You will loose some mph out on the road but it will be better off road.

[R.E.D]

How much mph would I be loosing...the truck is very fast off a start...my brother in my ch 427 cant even give pose a challenge. .I like that ability of a 350 leaving higher hp trucks in the dust..

[GreenGiant2]

i think i can run 65 mph with my 300L with a 2080 trans and 4.64 rears. I think maybe 62

[R.E.D]

I hit 65 with ease , even loaded. ..I have gotten her up to 67 in the hwy..im amazed how 7 gear takes me from 35mph to 53 mph then 8th gear takes care of the rest...

[j hancock]

Yes, your truck is fast with 4.17's and a 2090 giving a final drive of 2.96.

You won't loose much, 4-6 mph probably.

Was the truck built as a dump?

[R.E.D]

Im not entirely sure..but she has a short wheel base..loaded or unloaded the rear axles travel alot...thats why im lookin for diffs with transverse torque rod bracket...

[j hancock]

The transverse rod will tighten things up.

Are the trunion bushings and the spring box rubbers good? If they are worn out, adding the transverse rod won't solve it.

[R.E.D]

Yes all replaced 4 months ago...would I hav3 to put a transverse torque rod in the front axle also?

[j hancock]

The factory design is one transverse rod on the rear axle.

[R.E.D]

I was wondering cuz the guy that will sell me the diffs has a couple of dms or r models with transverse rods in both axles..

[R.E.D]

This guy has loads of mack bogies stacked on top of each other

[bullhusk]

My Superliner with the T2090 4.64 11R24.5 had no prob goin in the mid 70's

BULLHUSK

[j hancock]

Not familiar with a front axle transverse torque arm on a Mack camelback?

If the yard has what you want, go for it.

[R.E.D]

Sure will...I just want be sure its going to be a direct drop in to the carrier...