dana 35 hops. what do i need for the 8.8 discs to work?

[JeepcoMJ]

i think a spider gear is broken, or ring gear, or cracked, or whatever. but my rear end jerks and hops...i'll know more tomorrow when I pull the cover off.

 

I can get an 8.8 rear end from a 98 ford with disc brakes...complete end to end for cheap. what do I need to do to my brake lines and ebrake lines to make this work?

 

I already know what I need for the driveshaft so i'm not interested in info on that, and i already know it's 1" narrower so no info needed on what i gotta do there.

 

all i need to know is either A. what could be the symptom of my rear end...it's not making noises except when it jerks and hops, which is every once in a while when i give it a bit of gas.

 

or B. what's needed for the rear discs to function. It's already got an xj proportioning valve...but idk if the master cylinder is good enough for discs, what I need, if my lines are up to par, etc.

[pingpong]

To get the 8.8 to work in the back of the MJ you are going to need perches, and wheel spacers.

 

For the brakes I did the xj prop valve, and bled the brakes really well, and no issues

 

This is the article I based my swap on yrs ago, I kinda used it as a guide

http://www.jedi.com/obiwan/jeep/ford88.html

[87manche]

for the brakes, you'll need a passenger side brake hose for the drivers side, so you can use a seperate junction block, rather than the ford part that has the drivers side soft line molded into the brass block.

You'll need spicer flange adapter, PN is 2-2-279 I think.

Head down to the dealership and get some mopar performance perches.

 

That's about it. I'm in the middle of this swap myself after two dana 35's blew up in a week.

[Rokhound]

for the brakes, you'll need a passenger side brake hose for the drivers side, so you can use a seperate junction block, rather than the ford part that has the drivers side soft line molded into the brass block.

You'll need spicer flange adapter, PN is 2-2-279 I think.

Head down to the dealership and get some mopar performance perches.

 

That's about it. I'm in the middle of this swap myself after two dana 35's blew up in a week.

 

in stead of using the Spicer Flange I think you can use a ranger flange from an a 8.8 I think that is what mine is and you can still use the same u-joint :dunno:

[Pete M]

Don't quote me on it, but I think I remember reading that the Aerostar 8.8 also has the right flange adapter size.

[JeepcoMJ]

it blew the spider gears...3 of them are missing a combined 7 teeth...i could only find 6 teeth and some other shards.

 

 

 

so for now, I'm pushing the roll pin out, sliding the spiders out, and then I'm gonna do the same on my other 86 and swap spiders...i need it driving and that won't cost any $$$.

 

it's got 3.53 gears...ratio of 46 ring to 13 pinion. so I'm debating on what to do at the moment...the 8.8 i was getting is 3.73 gears. I will probably get it and perhaps my other 86 has 3.73's so I can just swap the front carrier? we'll see...but I think i DEFINITELY need the rear upgrade with how i drive...

[Pete M]

Well, you can't "just" swap carriers and gears, you'd need to re-setup the gears. How cheap are you getting this axle? I've not found any evidence that 3.73 gears were ever offered in an MJ. They were offered in various years of XJ, but they can be very hard to find. It may be difficult to find a matching front axle. 3.55s were offered in Explorers, so maybe it would be better to wait and get one that has the right gears. Or get a 4.10 one and go for even better gears. :D

[mjeff87]

drop the spiders, lunchbox it and see what else you can break :brows:

 

Best bet to find a 3.73 D30 is a 2.5 with auto (904, not an AW4)

 

Jeff

[GirsMJ86]

well my 86 x had 3.73s so you might get lucky and yours might have that in it. but either way i say upgrade, upgrade, upgrade.

 

Alex

[feerocknok]

drop the spiders, lunchbox it and see what else you can break :brows:

 

Best bet to find a 3.73 D30 is a 2.5 with auto (904, not an AW4)

 

Jeff

We've gotta figure out this spec, cause my 2.5 -> 904 has 4.10s. '86s are so difficult to find info on!

 

Who would've thought your 3.8 would blow up a 35?!

 

I don't really have any tech to add to this thread, but a rear axle swap from a 35 to 35 is So easy and quick, just grab a 35 off of one of your 14 MJs and throw it in till you can upgrade.

 

No one's addressed his brake questions...

[JeepcoMJ]

the other 86 had 3.54 gears i believe...but i'm going by the stamp on the ring saying 39 and 11. I'll count later to be sure...the spiders are matching between the two.

 

so for now, i'm putting the good ones in my truck, and the junk ones (which still sorta work) in the 86. that way I can DD and if i need to move the 86 I can.

[mjeff87]

That's just been my experience seeing them in the junkyards, plus it burnt me waaaay back when I first started gathering parts for my 4WD conversion.....I gave a guy $150 for a D30 under a junker 86 MJ he had. The only difference between his and mine was it was an auto and mine was a 5 speed. I just ASSumed :oops: it was a 4.10. I got hosed.....

 

I've also seen them in front of 4.0/AX15's, with tow package, but like Pete said they're fairly rare. I can count on one hand all of the 3.73's I've come across in the last couple years.

 

Jeff

[JeepcoMJ]

We've gotta figure out this spec, cause my 2.5 -> 904 has 4.10s. '86s are so difficult to find info on!

 

Who would've thought your 3.8 would blow up a 35?!

 

I don't really have any tech to add to this thread, but a rear axle swap from a 35 to 35 is So easy and quick, just grab a 35 off of one of your 14 MJs and throw it in till you can upgrade.

 

No one's addressed his brake questions...

 

lol. my 3.8 has more balls than a stock 4.0 :brows: ...i KNEW it was gonna blow.

(it's 200hp and 225 ft/lbs. torque stock...this one has the cold air, my custom headers which allow higher flow, high flow exhaust all the way through, AND a coil pack upgrade/reprogrammed computer to give it more...I'm sure if I dyno tested it she'd be about 215 horse and about 250 torque or somewhere in there)

 

I'm just swapping ring gears out of a parts truck...less work and no brake bleeding :D

 

anyone ever scrap the roll pin and put a bolt in? I'm thinking of threading the part where the roll pin goes on the spider...I don't like having to remove the bearing caps to punch out the roll pin.

[JeepcoMJ]

That's just been my experience seeing them in the junkyards, plus it burnt me waaaay back when I first started gathering parts for my 4WD conversion.....I gave a guy $150 for a D30 under a junker 86 MJ he had. The only difference between his and mine was it was an auto and mine was a 5 speed. I just ASSumed :oops: it was a 4.10. I got hosed.....

 

I've also seen them in front of 4.0/AX15's, with tow package, but like Pete said they're fairly rare. I can count on one hand all of the 3.73's I've come across in the last couple years.

 

Jeff

 

hmm...so you're saying i need a HP dana 44 front axle w/ the same gears as the 8.8 then? 8) :brows:

[mjcanoe]

JeepcoMJ, According to OEM manual, 3.54:1 would be 46 count on ring, 13 count on pinion. This is from7/85 mj manual. The 3.55:1 will work also if you have one. I blew out 3 sets of spider gears in my '86 w/a swapped in, modified HO (not stroker), last set I took out destroyed the carrier. I put in 4.10/4.11 combo out of an '86 xj which I rebuilt w/brgs.,R&P, etc. & for 2 yrs now no trouble. My mj is 4wd L/B & Idrive it hard. I do have oem manuals if you need info for set-up.

 

mjcanaoe

[87manche]

jeepco, I've got a spare carrier for the D35, that had 3.73's on it, the spiders are in good shape. You can have it saturday if you want it.

it would save you the hassle of tearing it out of the other axle anyway.

[CEThomas]

pingpong answered the brake question with this link:

 

http://www.jedi.com/obiwan/jeep/ford88.html

 

Has all you need to know :D

 

Charles

[JeepcoMJ]

JeepcoMJ, According to OEM manual, 3.54:1 would be 46 count on ring, 13 count on pinion. This is from7/85 mj manual. The 3.55:1 will work also if you have one. I blew out 3 sets of spider gears in my '86 w/a swapped in, modified HO (not stroker), last set I took out destroyed the carrier. I put in 4.10/4.11 combo out of an '86 xj which I rebuilt w/brgs.,R&P, etc. & for 2 yrs now no trouble. My mj is 4wd L/B & Idrive it hard. I do have oem manuals if you need info for set-up.

 

mjcanaoe

 

 

it's 3.538 something...so yeah, 3.54. my cell phone showed 3.53...but yes, I've got 3.54 gears!

 

the carrier was OK, but the spiders were junk...still good enough to get from a to b...with hopping.

 

here's what the spiders that i wrecked

so I put these in out of my other 86 and put the wrecked ones back in it so i can move it on the property

 

the other truck has 39 to 11 teeth I believe....not sure if that's right I didn't count, just went by some of the numbers...not sure they're the right ones.

 

but the 3800 is fixed and operational..the rear axle needs a new front seal, but I couldn't get the yoke bolt off even with the torque wrench so that's another day.

[JeepcoMJ]

jeepco, I've got a spare carrier for the D35, that had 3.73's on it, the spiders are in good shape. You can have it saturday if you want it.

it would save you the hassle of tearing it out of the other axle anyway.

 

I could use that carrier to get tatersalad operational again...shoot me a pm if you are interested in getting rid of it. :D

[mjcanoe]

JeepcoMJ, Don't need/want torque wrench for removal, long bar will do the job to remove, maybe some penetrating oil will help. Torque is for set up & is very important to do the set-up properly.

 

mjcanoe

[JeepcoMJ]

I meant a torque gun...high power 1/2 inch drive. couldn't get it off w/ that, nor a breaker bar :(

[mjcanoe]

JeepcoMJ, the factory set- up procedure did not use a specified torque for pinion nut, since it directed tech's to use set specs on pinion preload. You tighten pinion retaining nut to a certain "rolling torque' w/inch pound torque wrench. They used a preload spacer, which was a 1 time use. You may be suffering from the salt plague. Try to heat up nut with torch, medium heat@ 1st then use breaker bar. Yoke must be held in place firmly.

 

mjcanoe

[JeepcoMJ]

like i said, what i tried didn't work. breaker bar didn't work, and ironically in as big a shop as I have, i didn't have space to get it in...so it's driving the way it is for now. I'll get it out by heating it w/ a torch. have a new nut so worse comes to worse I can use a hammer and chisel to get it loose.

 

i've got a few tricks up my sleeve, but just no space to do it...fixing 3 lawnmowers, got the t-bird in the way, my bunch of snowmobiles to be parted out, etc.

 

so i'll git-r-done sometime in the next 500 miles. i'm doing the oil change on the pavement tomorrow...which i thought would be easy, except that with the 3.8 while you DO have easy access to the oil filter, you DON'T have easy access for it to drain...i have to place a small pan under the oil filter so it doesn't run all over the skid plate and leak from 5 different places on that...no biggy, i don't even have to get under it for that :D just to undo and retighten the drain plug :D yay 3800!

 

Lt1 coming soon...j/k but i should have done that from the start...