I'm gathering supplies to start to do some maintance on old Amigo-2k and I think I have put in 75-90 weight gear oil in the rear the last 2 times. Does this sound correct since I live in Wisconsin.

I would like to switch to synthetic but it seems like I can never find it at any of the stores around here.

I have the Fel Pro # per the FAQ's so that shouldn't be a problem.

that is what i use. i have trouble finding it to. i usually have to go to about 4-5 parts stores to scare up 4 bottles of 75w-90 synthetic gear oil.:wtf: so i end up putting in a couple of brands of synthetic. i have also noticed every auto parts store hear doesn't stock alot of selection of gear oil, and the stuff they do have usually are only 2 deep on the shelf. i guess it is more popular to change your oil in your engine then your diffs.
one soultion might be to try use online purchasing for any of the major parts houses. that might work better.:)

I used valvoline SynPower 75w90 in mine. Should be fine for the temps you get there. We get pretty much the same temps, just not for as long.

I think I had to go to 2 different Checkers to get enough but I think all the auto parts stores carry it. It also doesnt need any additional LSD addatives if you have LSD in yours.

I just got back from Weaver auto parts and they had a couple of cases of it. So I'm set. Nice evening to hang out on the ground!

IIRC, I believe we have the 80-90wt in ours - we were doing a lot of towing with it though.

I'm using Amsoil 75-90 in the front and back.

Alight it is in. I took it for a spin and then parked it. an hour later there where 3-4 drips on the ground. So I went around it again (criss-cross) with my socket wrench (with an 18" bar on the end) to snug it up again. This morning there were 2-3 more drips on the ground. So I don't know if the fel pro gasket needs some time and heat to seal it up or if the synthetic is just to slippery and it find the right spot to get out.

All surfaces were super clean (the last 2 changes I have used Fel Pro gaskets).

Time will tell ...

when i did mine i pumped the front. but in the rear i coun't get the pump in the rear (finned) cover, so off it came. i sprayed the inside with brake clean and mating surface. then i got some rtv (oil resistant) and sealed the rear up.
so far so good. last resort i guess if you can't get a gasket to seal. mike

p.s. i also lightly hit the mating surface with a roloc pad on a die grinder

I have a fel pro gasket on mine as well (though with a chrome steel cover) and it leaks a bit. Next time I do the job I'm going to put a thin coat of rtv on the gasket. Should take care of the problem.

I also get a bit of weeping through the seals in front and rear diffs. Mine were neglected though, the oil had never been changed in them until I bought it (88k miles). Doesnt weep enough to drip though, just enough to see it.

from whati have read...it's not very hard to change the diff fluid, right.

any special thing to be leary of? i may be doing this soon before the winter months start coming in.

The rear one is the worst. Since it doesnt have a drain plug you have to pop the rear cover loose to drain it. Make sure you have a big enough drain pan. Also if it hasnt been removed before it can be tough breaking the seal of the factory rtv. I just loosened all the bolts at first, then popped it loose and let it drain before fully removing the bolts. It doesnt all come rushing out that way.

Also I had to loosen one side of the latteral (panhard) bar and pull it back. But that was because I was completly removing the cover and there isnt enough clearance. I changed to a steel cover when I did the oil in mine.

The front is easier, the bottom bolt on the 3rd member is also the drain plug.

I'll have to keep an eye on it. The last 2 times with dino gear oil I never had any issues with leaks.

I dunno why, but your chances of a leak always seem to be greater using rear diff cover gaskets as opposed to RTV alone. I just use RTV on the covers. Ryan, also make sure your rear diff vent is not plugged.

Joel

The plug is good but I'll check it again. I went home for lunch and went over all the bolts again and tighten them all a bit more. When I pulled into the lot at work I got out and there was a drip 3 feet behind the truck and one already under the diffy. So it looks like it is getting wrose now. I'll tighten it a bit more and then I'll have to redo it. If I redo it I'm switching back to dino gear oil, since it is a lot cheaper the synthetic (cost me 30.50 for 2 quarts of syn and a gasket, and my dealer charges 35.50 to change the rear diffy fluid).

-Ryan

... and to the dealer it goes. I went out this evening to tighten it a little more and then snap! there goes a bolt ....... it sucks. ....

So I'll have to call up tommorow to see if I can take it in or Monday or Tuesday. Open up the wallet and pay .....

That does suck. I thought about snapping some of the rustier ones on the back of the Jeep when I did it a couple of months ago.

I'll get new bolts when I do the Rodeo again. It looks like the pinion seal is a little leaky, too, but I don't know if I want to tackle that...

It is going in on Monday morning. I went there first thing today and they are all booked up. the funny thing is i think it has stopped leaking ..... DOH!

... and to the dealer it goes. I went out this evening to tighten it a little more and then snap! there goes a bolt ....... it sucks.

You know thats why they make torque wrenches right? :rofl:

I just torque to spec, if it leaks it leaks. I just wait till next time and rtv it. I hate leaks and always try to fix them but not at the risk of breaking off bolts, I deal with enough of those at work and it just sucks.

Torque wrench I think is on my Christmas list this year.....

Well it looks like it is going to cost me 56 bucks. And that is just to drill out the old, re-tap and screw in the new. I've done this myself before on other non-important things (radiator brackets...) on other cars, so I didn't want to test me skills out on this.

They also told me that it is still leaking (I know ....), and that they typically just suck out the old and put in new ... Oh well I'll just keep topping it off and next year when I take it in to have the tranny filter replaced I'll have them replace the seal too.

-Ryan

That's not too bad. It is good to drop the cover and clean things out in there periodically.

That's not too bad. It is good to drop the cover and clean things out in there periodically.

Yup, I agree. Now I understand why they charge 72.50 (with coupin) for changing front and rear diffy gear oil.

Yup, I agree. Now I understand why they charge 72.50 (with coupin) for changing front and rear diffy gear oil.

Amigo- I've only done maybe 3-4 diff oil changes on various vehicles, and the first 2 I used a gasket for the cover. They leaked. RTV alone = no leaks. I'll never use a gasket for the diff cover again. Most vehicles (my 2002 rodeo and 2005 TB included) came with RTV from the factory. I'm getting ready to do diffs on the TB soon.:uhoh:

Joel

Cool.

I'm thinking about try again in the next couple of weeks because I don't like the oil spots on the driveway ....

I'll second not using a gasket. When I pulled the front and rear on the Jeep, I found no gaskets, but the factory service manual clearly shows one for each. I just cleaned all the old gasket material off, wire brushed the outside of the covers and shot them with some flat black paint, sprayed out the internals with some brake cleaner, RTV'd the cover with the red stuff, and closed it up. I tried to torque the bolts evenly and to what I thought was spec. No leaks. Here's a good writeup...
http://stu-offroad.com/misc/diff-1.htm

and the saga continues ....

So today I took the day off to head to a friends house to help with some landscapeing. I have a small trailer that I brought with to help haul some of the bushes and dirt and such. When I get there I saw the trailer chains were covered in gear oil and there were splatter of gear oil all over the front of the trailer.

So on my way home I picked up 2 qts of gear oil and some gasket maker stuff, then I stopped at harbor Frieght and picked up a 15 dollar torque wrench.

So I drain and and I take the cover off. What do I find??? One of the brake line brackets was behind the stupid cover! That is why it was leaking! So I decide forget this make a gasket crap I want a fel pro one again! So I jump in my old school bug and hit up two parts stores to find one.

I button it all up and start the bolts with a normal wrench. Then I start up with the torque wrench. I set it to 30 ft lbs per the manual (I checked, please check for me if you can). And man did it seem like a lot of torque! So i backed it to 20 ft lbs and I could move all the bolts and little and then click, the wrench did its job. So then I moved it to 25 ft lbs. i go around the cover again ...

and then it happens ... SNAP!!!!!!!!!!!!!!! Mother Blanker!

I stop.

I reverse it and I'm able to screw out the whole thing out since there is still enough metal. ok.

So I head to True Value hardware and come up empty.

I stop at the parts store next to it. Nothing and they tell me to go to harbor freight. i go there, nothing.

So at 5:45 I head to the dealer. I pull into the garage (with the bug) and there is just one service guy there. I have bolt in hand and ask for help. So we walk throught the service bays to the bins and we can't find the right bolt. So he recomended bringing in the other one they put in and then they can match it up tomorrow. ...

So does my 15 dollar torque wrench suck or did I over stress the bolts last time?

So far I spent 125 bucks trying to change the rear gear oil ...

I'm hoping that I have the bolt in hand tomorrow and then i'm leak free.

More tomorrow ....

My FSM and AllData both say 30 ft. lbs. (they have the same pic) but my haynes manual says 20 ft. lbs. Mine is torqued to 20 since I only had the Haynes manual when I did mine. :dunno:

Hopefully you didnt have to argue with the parts monkey about the gasket. The one at napa swore up and down that my rodeo didnt have a D44 in it. I think when I do mine again I'm going to go with a thin coat of rtv on each side of the felpro gasket, then only torque to 20 ft lbs.

I never mention what the gakset is for. i just ask for RDS6629.

I read plenty of stories over the years about folks looking for fel pro gaskets at part stores and the parts guys saying, An isuzu with a Dana 44?!? No way that is not possible.

I think 20 ft lbs is probably more like the right number ... Thanks for looking it up!

Oh man that sucks!:banghead: Ryan, were those bolts tight when you first removed them? A lot of manufacturers loctite the diff cover bolts from the factory & they get kinda stressed the first time you remove them. I thought the bolts on my trailblazer were going to snap on removal.:disappoin

Joel

i didn't use a torque wrench just snugged them up. yea you spent 120$ but look at the knowledge you now have, as well as the experience! (priceless) but i am the type of guy that likes the journey more than the vacation destination!

So I drain and and I take the cover off. What do I find??? One of the brake line brackets was behind the stupid cover! That is why it was leaking!

Beautiful. $56 to get it half right. You're changing all 10 bolts, no?

I know. I told them when I took it in last week, to take the cover off, drill and tap. gasket, cover, oil. All they did was drill and tap.

The thing that I'm worried about now is making sure the new bolt fits into the old treads. I tried the new bolt in the orginal treads and I can turn it 4 times and then it stops. I would think 4 turns means I'm good and now when I put the wrench on it it should turn in. I'm planing on asking that question tomorrow for sure.

I would love to change all the bolts, but I would like to make sure I have the right ones first (the one new bolt had 2 washers on it, one crush washer and one normal). It seems kind of odd that a parts store doesn't carry such on item?

I hope all is well tomorrow and then I can switch out a could of other things in the next couple of weeks (h20, s-belt, and power steering fluid).

-Ryan

Ryan, were those bolts tight when you first removed them? A lot of manufacturers loctite the diff cover bolts from the factory & they get kinda stressed the first time you remove them.
Joel

Well this is the third time I have change the rear gear oil (15k, 45k and now 75k).