Swapping in the SureGrip

[92whitedak]

8.25" 3.55:1 ratioed peg leg. I'm tired of seeing only ONE huge plume of smoke pouring from the back end. What will it take (cost and work) for me to swap in a 3.55 (maybe 3.91) with a suregrip. I don't have to manipulate the housing, do I? Any help would be greatly appreciated. I'd imagine the cost is fairly low, no? Or should I just go junk yard hopping and find an 8.25" suregrip setup and pull it. What companys offer a suregrip unit and some taller gears for the 8 1/4. Thanks felluhs.

-Fox

[drag-n-cuda]

92whitedak,
I wouldn't even use an 8.25" if you're making decent power, 375-400 hp. I'm breaking 8.75" parts, but I also race and drop the clutch (manual) at 4500 - 5000 at the track.

drag-n

[JVMopar]

Randy's ring and pinion has a 8.25 Trac-loc clutch type posi for $177. I'm going to be going this route this summer with mine. And it's rebuildable so that's a plus

[92whitedak]

I like the rebuildable aspect. Thats nice. And will keep me busy on boring days Drag-n-cuda, I'm not making anywhere NEAR that amount of power. If anything, I'm pushing 220 in my 3.9 v6 dakota. No need to worry. Hey JV, is that going in your dakota? If I recall, we both have the same one (92 2wd 3.9 magnum) Maybe we can bounce this idea off one another. Thanks for the replies. Anyone else?

-Fox

[JVMopar]

Yes that's for my dakota. And yes it's a '92 2wd 3.9L A-500 8.25 3.55:1 extended cab. And it's got 170,800 miles on it. It's been a fantastic truck.

My dad bought it new and gave it to me with 154,000 miles on it. The only things ever done to it was a water pump, starter, and radiator. Everything was just maintenance like brakes, fluid changes etc.

It's kinda like the song goes "the older she gets the slower we go, but there ain't nothin wrong with the radio..." Empty it's fine but with any weight in it, she becomes a real dog. 119 hp at the wheels

One of these days I just might replace my stretched timing chain and fix that plugged cat, but that's all in due time.

Personally I'm going to rebuild the A-500 this summer and put in a slightly worked over 360. I was thinking of dropping the fuel injection but I'm still debating that one. I'm also going to convert from the 6 lug to the 5 lug because of more rim options. And I've got a gallon of lime light green to go on it. Then later on in life put a keilser 5-speed in it. Toys toys toys

[92whitedak]

Interesting that we are both at the same stage for the SAME exact truck. Mine is a 92 2wd a500 8.25" 3.55:1 extended cab. LS. White/grey two tone. And interestingly enough, i've got the damned chain tap (Have parts, install next weekend?), shot cat (7k miles old. WHAT IS IT WITH THE DAKOTAS AND KILLING CATS!), trans is slipping in the 2-3 overlap. And just broke 104K miles. Hey, when you drive in reverse, does your speedo move counter-clockwise? Check it out And your rear, its open, right? Any chance you'd know about swapping in a posi and the tools I would need/books I would have to read into? I've found the wheels I like so I'll be sticking with the 6 lug, even though it sucks a lot, I agree. I'm definately going to have to remember your user name so when I can't remember "where that little screw from the interior goes", you'll be the first person I contact

-Fox Deacon

[6 packin]

Its not real difficult to set up gears or whatever. The tools makes the job done right. Just follow the suggested install guide lines with the new ring and pinion to the letter. The pinion depth in the most important and difficult thing to set. Assmebly and disassembly a few times to get it right, but a must. Backlash, bearing preload also is important for a trouble & and noise free gear. I suggest running a Syntehtic gear lube also. I nhave found the Richmond gears to be spongy, to take the shock of drag racing, the tend to howl more than factory gears, espeically when dealing with gears like 4.30's and 4.88's. Even though you follow the directions to a the letter I have had them make some noise, a switch to a synthetic usually takes care of it.

[92whitedak]

6 packin - like I said, I've never done anything like this before. I've never even had a rear end open. But I don't want to take this to a shop. How do I check things like pinion and gear depth, backlash, bearting preload? Things like that? Can you run down like, how I would go about it, step by step, but roughly. (i.e - Remove rear diff cover, unscrew such and such, slide out such and such) Thanks if you can. That'd be the ultimate. Thanks again.

-Fox Deacon

[JVMopar]

Well my cat is the original one so 170,000 isn't too bad (it's been ratteling since 120k) In fact I just replaced the original O2 sensor about 5k ago. It was still functioning fine (I could see it switching on the scan tool) but I had a new one so I just put it in.

Yes the rearend is open. Depending on how the gears look I just may leave them in. So putting in the posi should be easy. I'm not too worried about it but I'm going to be replacing all the bearing because of the mileage. I just need to get all the bearing preloads set and backlash set and shouldn't have any problems.

There's only one way to learn and that's jump in.
Since I have back up vehicles I don't worry about having one down for a while.

[6 packin]

You need a dial indicator and a magnetic base. Some powder compound for the teeth pattern. Usually after you take the differential apart making sure that you mark the bearing caps, so they can go back the same place, they look like main bearing caps and saddles. After the case is dissasembled and cleaned, you measure of the main saddle where the bolts attach to find a certian depth. Like 3.73 inches usually marked on the tip of the pinion. Lets say after installing the pinion and set the correct preload (usually measure in inch pounds Torque wrench) you measure 3.62 then you know a set of various shims which must total to .011 thousands placed between the pinion and closest bearing (rear pinion bearing), to bring it into the desired specs. You can see now why you may be disassembling it several times and measuring to get what you want. The pinion depth is very critical, and 75% of the job. After that is pretty much setting the posi/differential in there and finding the proper backlash. Which also is measure with the dial indicator. Its actually the clearance or movement of rocking back and fourth the ring gear untill contact of the pinion, not moving the pinion also, like end play! Make sure you rotate the gear around cheching in no less than 5 different spots. There will be spots with more/less backlash. You whanna set it up in clearance in the tightest spot, making sure that it still in spec at the looses also. The back lash is set through cap adjusters the set both backlash and bearing preload also in the diffeferntial caps. Like srewing a nut inward, torward of the ring gear will decrease backlash. after back lash is close, running the other side cap/adjuster nut in will, both keep the backlash where it is now (when tightening the other side in) and set bearing preload at the same time. Locking it in place while setting backlash and bearing preload on both sides. After all that the marking compound is brushed on the ring gear rolling it in/through the pinion to see the wear pattern on the gears. Things to look for here is just a vitial as everything else. It will insure proper pinion depth and backlash. To little backlash will be shown, the teeth will be meshing to deep or to shallow between the two. If the pinion depth is off the ring gear will not be riding deep enough or too depth on the pinion. Haynes manuals should have pics of what to look for. remeber there is two sides of the teeth also, heel, and toe. the pattern must be perfect. Or it will make noise (howl) or bottom out in the teeth, which would result in dusting the gears at 99 times the rate you put it togather in. This is not a guide there is actually way moe to it than this, but this will give you a idea of the path ahead. It doesnt matter what rearend a 10 bolt chebby, Dana 60, or 80 ton Eaton rears in Dump Trucks they all setup the same way and principle.
I suggest getting some books or service manuals and following them to a T. The out come will always be better. And you wont have wasted time and money to learn the hard way as I have. I have dusted a few also, $hit happens