Ring & Pinion Guidance

[eschaider]

A Little guidance …

‘Ever since I blew up my ring and pinion and replaced it with new parts I have been experiencing problems. The rear end is an 8.8” Ford. I used an 8.5” Dana 44 ring and pinion to save weight. I made some custom spacers out of Home Depot washers to get the new smaller, lighter, higher performance ring gear closer to the pinion in the Ford housing.

I am now on my fourth Dana 44 R&P. It seems the Dana gears are very sensitive to foreign material from the previously failed ring and pinion getting between the gear teeth. When the older broken teeth get between the newer teeth on the fresh R&P the car exhibits a significant amount of jerking behavior along with a lot of noise, making the car less attractive to drive now.

I have also discovered those gear ratios with a larger pinion gear tooth count last longer. There can be a considerable improvement in drive time because it takes more time to break off all the additional teeth compared to the gear sets with a smaller pinion tooth count.

It seems to me that the Dana gear sets are much too finicky about old broken gear teeth in the differential. If you had to clean out the diff housing each time you break a ring and pinion before reassembling new gears in the rear end this could get very old, very fast.

The silver lining in this whole event is the much-improved acceleration and overall performance of the car with the smaller 8.5” ring gear. The reduction in angular momentum and rotational kinetic energy with the smaller ring gear is immediately noticeable in the seat of your pants. It actually feels really good until those older broken gear teeth start circulating.

Does anyone have any suggestions for how to mitigate the noise and jerkiness while driving the car when those old broken teeth get between the teeth on the new ring and pinion. BTW it is additionally aggravating because when it happens in lower gears it has broken teeth in the transmission in second gear and also in fifth gear overdrive — which like the rear end just seems to get worse each time they fail.

[Tom Wells]

Ed,

There is a solution: if you have access to an earthmover tire innertube you can make an energy-absorbent driveshaft!

Simply cut a lengthy strip of the tube 8" wide in a spiral fashion. Then wind the tube the same way the rubber band is wound in a model airplane. After you get enough turns in it, you can clamp each end into prefabricated transmission tailshaft and rear axle pinion gear clamps.

The advantage given by this arrangement is most noticeable during launch; you footbrake while you are feeding enough throttle to wind the rubber driveshaft as tightly as possible, storing energy to add to your engine's torque when you release the brake!

Another advantage is complete vibration isolation of the rest of the car from the rear axle, making its performance as smooth as possible.

Hope this helps,

Tom

[eschaider]

Tom, this has real potential!

I like the idea of repurposing earthmover tire inner tubes rather than disposing of them and potentially adding to the global warming from all the heat of combustion not to mention the nasty carbon emissions from burning the rubber!

Additionally, the slingshot effect as they unwind coming out of a turn or after launch is very appealing. Now I need to give a little thought about how to quickly re-tension them during the race in time to be ready for the next turn.

Shucks, I just remembered that I could also use this to mitigate the Trailing Torque Oversteer predisposition the car exhibits from time to time. I am not certain but the earthmover tire innertube mod might just be the USW (Ultimate Secret Weapon). Why didn't I think of this???

[Snake2998]

This reminds me of my wife's cousin who at 14 got hold of an old Morris Minor to use as a dune buggy and accidentally installed the diff upside down - went very well backwards with 4 backwards gears but only had one forwards gear.

[MAStuart]

I think you guys should be paying others to work on your cars! Is it the first of April?

[hauss]

For a minute, I thought you had suffered from a stroke.

[eschaider]

In a weak moment, I couldn't resist parodying the occasionally entertaining but fully confused threads we see on the site from time to time

[D_ranged]

Forgive me as I am fairly new on this site or at lest this is my first post, but when I broke a tooth or two on my Dana 44 in my Jeep, I took it to the local gas station and the guy there pumped in some STP and sawdust. No more noise……

Although I like the idea of an inner tube drive shaft.

[twobjshelbys]

Originally Posted by D_ranged

Forgive me as I am fairly new on this site or at lest this is my first post, but when I broke a tooth or two on my Dana 44 in my Jeep, I took it to the local gas station and the guy there pumped in some STP and sawdust. No more noise……

Although I like the idea of an inner tube drive shaft.

Did that package include a for sale sign?

[incoming]

Lots of banana peels and STP would get you through a car auction in the seventies.

Ever heard of a parts washer and a lot of brake cleaner to remove the FOD?

I really don't know where to go with this?

[D_ranged]

My poor attempt at humor, I actually replaced my Dana 44 for a Dana 60 with alloy gears after installing a 5.3 Chevy…..

[eschaider]

Originally Posted by D_ranged

My poor attempt at humor, I actually replaced my Dana 44 for a Dana 60 with alloy gears after installing a 5.3 Chevy…..

This is a far too serious a response. Another infraction of this order, in the competition, could incur a demerit ...


p.s. with a screen name like D_ranged you should certainly be capable of better

[Tom Wells]

Ed,

Uhh...

Wouldn't that be a D_merit?

Tom

[eschaider]

You're right Tom!

I missed that one!

[D_ranged]

The shame of it all, I feel D_ejected…….

[moore_rb]

Originally Posted by eschaider

It seems the Dana gears are very sensitive to foreign material from the previously failed ring and pinion getting between the gear teeth. When the older broken teeth get between the newer teeth on the fresh R&P the car exhibits a significant amount of jerking behavior along with a lot of noise, making the car less attractive to drive now.

Think, Ed- back to your high school chemistry class: Most metals dissolve into salts when exposed to extremely acidic PH levels.

So clearly, if the old broken R&P remnants are still solid enough to be damaging your new gear sets, then you CLEARLY haven't added enough Muriatic acid to the diff before breaking in the new gear set.

OH, and BTW- DON'T get duped into buying that ultra expensive acid from Royal Purple- All you are paying for is the brand name...

Just buy the generic acid from the pool department at Home Depot. A guy I know at Royal Purple says it's the exact same stuff...

[eschaider]

Robert,

I know the proper timing (and, of course, mixture) of the chicken fat and sawdust is critical to the continued quiet operation of the diff. Can you offer any insights into mixing the ingredients and the timing of these advanced service techniques?

[moore_rb]

Originally Posted by eschaider

Robert,

I know the proper timing (and, of course, mixture) of the chicken fat and sawdust is critical to the continued quiet operation of the diff. Can you offer any insights into mixing the ingredients and the timing of these advanced service techniques?

Well, since we're talking about differentials here, there are as many different techniques, as there are salty old gearheads who swear by them...

But since you asked, here's how it was passed along to me in 1985, by my first real car mentor...:

Step 1)- after liberally coating your new ring and pinion with rendered chicken fat (or olive oil if you are in a pinch) then rub the gears down liberally with a blend of garlic powder, black pepper, and non-iodized salt. place in the refrigerator overnight and allow to dry brine.

Step 2) pre-jube your differential bearings by using a turkey baster to pressure feed your raw, separated egg whites into the bearing crevices.

Step 3) - Install your new pinion gear into the snout of the carrier, being careful not to disturb your dry rub that you applied in step 1. slide the pinion yoke onto the pinion gear spline, and torque the pinion nut (in 3 stages) to a final torque setting of 782 ft/lbs.

Step 4)- install your new ring gear onto the carrier, again being mindful not to disturb the dry rub from step 1. Slide the carrier into the housing and liberally coat the bearing caps with Elmer's white glue- tighten the bearing cap bolts finger tight, then strike each one sharply and repeatedly with a small sledgehammer or hand drill, until the bolt heads are sufficiently rounded over, to the point that no wrench or socket will ever fit on them again.

Step 5) Now it's time to verify your drive and coast patterns (which is why it was important to keep the spice rub on your new gears intact) - You will need a 2nd vehicle for this, as well as a long rubber belt. You want to jack up the rear end of the 2nd vehicle, and run the rubber belt from the drive wheel of the 2nd vehicle, to the input yoke on the new diff (you may need to secure the diff in a vise for this)

Once the drive belt is in place, start the engine in the 2nd car, place the trans into the highest gear possible (overdrives work best) and rev it to no less than 5000rpm, but no more than 14,000 (we don't want to accidentally overwhelm the drivetrain in the 2nd car)

Now here's where it becomes more art than science.... You want to keep it spinning ONLY until the new gear set starts to take on a nice caramelized color, and begins emitting the unmistakable scent of a smoked brisket. At that point, shut everything down, remove the drive belt, and let the new diff cool down in a barrel full of crushed eucalyptus leaves.


Once it's cooled off, you can install it back in the car, and fill it with your favorite gear lubricant (mine is a 50/50 blend of finely shredded montery jack cheese, and KY surgical jelly).

That's how I've been doing it for 37 years now...

Now if you'll excuse me, for some reason I am really hungry for some barbeque...

[eschaider]

I knew I was doing something wrong, Robert! I not only missed the caramelized coloring on the gear tooth faces when I was verifying the drive and coast patterns but I also forgot to use the Turkey baster!

This R&P install tech is really sophisticated and easy to mess up. Thanks for the detailed instructional walk through — it really helps