whole bottom half of front differential covered in oil...

[Black_Bravada]

Sorry sorry if this is covered on another post already...I can't find anything helpful...just hit and miss ideas...

Anyways my front differential appears to be leaking pretty bad...and it does the whole binding/crow hop thing...so I took it to my mechanic..brought my 4 quarts of Mobil 1 75w-90 synthetic....well he changed out the rear differential.. but when he got to the front he said it appears that I have a pinion seal burst or leaking..whatever. SO anyways he said he can't do anything to it also saying the front end takes a different type of gear oil?? I say BS on that, right??? (I own a Haynes Repair Manual) Front and rear same fluids, just different amounts..anyways he referred me to a local transmission shop to to repair it..

The thing I need to know is what can I do in the meantime before I'm able to take it in on Monday or Tuesday?? Can I fill up the front differential with my 75w-90 synthetic???

Also has Anyone else have the job done?? What did it cost ya?? Because if this is crazy expensive and doesn't fix my binding/Crow hop... I'm about to trade the junky thing in....my mechanic also measured around my tire saying how a couple of them have threadwear off within a fraction of an inch????? Really? So he said maybe new tires to fix crowhop? Really??? I've owned this thing for 1 year and have stuck tons of money in it...

I have put a new fan clutch in, replaced leaking fuel filter, bought new air springs for it (didn't fix problem) bought a new coil spring/shock kit, then awd wasn't working, changed out transfer case fluid, still nothing so I bought a new transfer case motor, (works better in snow, but still seams hit and miss, months later I changed out the transfer case fluid again...still binding..then I find out about all this leaking in front differential....

Any help any help?? Suggestions?? I don't want my truck to get destroyed, don't wanna keep sticking huge money into it...

 

[Sparky]

Front and rear diffs take the same gear oil. Nothing special about it.

 

[Black_Bravada]

Front and rear diffs take the same gear oil. Nothing special about it.

Ha!! I knew that...don't know why my mechanic told me that!!! Anyways so I can safely fill it up cuz of course its now low, till I take it in??? Also would the front differential now low on oil cause my slow turning wheel crow hopping/binding??? Not just the transfer case and all those components can cause that right?? I've changed out my transfer case fluid twice within a year both times drained out nice and clean, and new transfer case motor...

 

[Black_Bravada]

Also if it is indeed just a bad pinion seal that shouldn't cost me too much to have this transmission shop replace it then right??? Because you don't have to take out the whole differential unit right??? Just stressed bought this 1 year ago and my GF's stupid Saturn at the same time needs suspension work!!! Feeling stressed!!

 

[The_Roadie]

Crow hopping pretty much has to have the transfer case as a root cause. Either the encoder motor putting the clutches at the wrong position, or grabby clutches from low/old fluid or damage caused in the past.

 

[Black_Bravada]

Crow hopping pretty much has to have the transfer case as a root cause. Either the encoder motor putting the clutches at the wrong position, or grabby clutches from low/old fluid or damage caused in the past.

I see.....so when I bought my new encoder motor back in winter and put it in...there's a possibility I put it in wrong??? I remember it took a little work lining up the little gears other than that and the damn plug went in pretty easy... like I said when I put the new motor in it was way better in snow...and both times i drained the transfer case fluid all that came out was the nice clean looking blue auto-trak II fluid..and also my mechanic measured the tire around the whole tire wear...saying one or two were off a fraction of an inch???? Would that matter??? They are really nice Michelin's!!! To the eye they all look evenly worn barely also...really nice still

I just don't know how much more money I can throw at this thing!!

 

[The_Roadie]

Competent use of a high end scan tool (GM Tech 2 or equivalent) could command the encoder motor through its range of motion and figure it out. Guessing and shotgunning can cost more in the long run.

 

[The_Roadie]

Wait. There should be no exposed gears in a motor swap. Can you describe more exactly what you bought and how you put it in?

 

[Black_Bravada]

Also for tire rotation which is best for my "awd" just front to back, same side?? Or criss-cross them??maybe try that out for the crowhopping after front pinion seal is fixed...

 

[Black_Bravada]

Wait. There should be no exposed gears in a motor swap. Can you describe more exactly what you bought and how you put it in?

You know what I mean when I go to line up the encoder motor to the transfer case...it only goes in one way...sorry not gears....I believe I slightly adjusted the end of the motor so it fit in...right??? That's fine???

 

[Black_Bravada]

I bought the dorman part # 600904 motor and put it in....you know.... sorry sorry I'm dumb...not gears...

 

[Black_Bravada]

I'm just thinking how my front differential is causing problems the same time as my crow hopping/ binding....gotta be the same fix!!!!

 

[The_Roadie]

If the front differential was locked from frozen/welded spider gears, it could cause crow-hopping. This is so rare I've only read about it once. Easy to troubleshoot if both front wheels are off the ground. Spin one. The other side should spin the other way. A welded diff will have them both spin the same way.

 

[seanpooh]

I too have a leaking front differential. It's leaking at the input driveshaft pinion (where the front drive shaft connects to from the transfer case). It's been leaking since 2007 or 2008.

I only leaks ever so slightly. It's not enough to drip onto the driveway but enough to coat the oil pan and skid plate. I check it every month and I don't have to add much.

I did ask the dealer how much they would charge... "$1000 because we have to drop the oil pan." I called BS on that one since the service manual states that all you have to do is remove the skid plate, front drive shaft and the rear steering gear crossmember. I rather remove the bolt, check oil and add and keep the $1000 in my pocket. I couldn't find the labor times though to give an approximation.

It is a pain in the arse to change that seal but the tranny shop should have a lift to make it easy. Just make sure they don't over charge and print out the instructions for them if you have to.

 

[Black_Bravada]

Alright cool I'll keep this posted up to date with the transmission shop looking at it, I surely can't be the only one with this same. Problem

 

[Playsinsnow]

If the front differential was locked from frozen/welded spider gears, it could cause crow-hopping. This is so rare I've only read about it once. Easy to troubleshoot if both front wheels are off the ground. Spin one. The other side should spin the other way. A welded diff will have them both spin the same way.

Alright cool I'll keep this posted up to date with the transmission shop looking at it, I surely can't be the only one with this same. Problem

Have you tried spinning a wheel with both the front wheels off the ground? The Roadie is the guru on these repairs. He has saved me $$$$ and he wants to save you some too! Do the troubleshooting he suggested and report back?

The dealer will bend you over. You can take the knowledge gained here and pass it on to your mechanic. I do for repairs that require tools I do not own.

 

[The_Roadie]

Also for tire rotation which is best for my "awd" just front to back, same side?? Or criss-cross them??maybe try that out for the crowhopping after front pinion seal is fixed...

Trust the Owners Manual.

 

[Black_Bravada]

Had a second mechanic look at it today, from a transmission shop, he too said most likely because all my tires have worn so differently... its most likely causing my slow crow hopping....they both measured around the tire....I forgot the measurements...but said they were all off, so I'm getting new tires on Wednesday....so I got off work today after confirming indead the front differential takes the same as rear, Mobil1 75w-90 synthetic LS, I drained out the front, made me happy about 1 quart of old looking smelly crap came out!! Filled her back up went for a test drive...and I swear it glides down the road...still a slight crow hop when turning slow and parking tho...small leak by pinion seal I'll get fixed up next Tuesday!!!

Edit: tires worn slightly enough you can't tell by looking at them, I owned it 1 year now and stupid me never rotated them!!!! So now it'll be religiously!!!

 

[Black_Bravada]

Hopefully directional tires are okay on my truck, 2002 Bravada "AWD" (A4WD)??? General Altimax HP??? 255/60r17.. Just keep rotating them front to back, same side....

Also: of course getting a 4 wheel alignment done on her...

 

[seanpooh]

If the Bravada is the same suspension as the Trailvoys, then you don't need the 4 wheel alignment. We have no adjustments in the rears, some cars do actually.

I know the dealerships WILL charge you the 4 wheel alignment just because it's a truck and that they can.

I got into it with the guys at Belletire asking why they charging me more and why they cannot adjust caster and camber.
Now they know every time I go in, they know not to give me an estimation sheet for parts and labor and always charge me for a 2 wheel alignment.

BTW, what was the estimate to get that pinion seal replaced?

 

[The_Roadie]

I do for repairs that require tools I do not own.

I usually use that as an excuse to BUY the tool I don't own. My Dad taught me that tactic. PS: When he died I inherited a TON of cool tools. Sadly, none were electronic - that's my specialty, not his.

 

[Sparky]

When something calls for a special tool that you'd only ever use once in your life I tend to try to make do with hammers and vise grips Results sometimes aren't always so great however

 

[Black_Bravada]

OK! Took my truck in tonight... after they brought it in they wanted to know why I was replacing my tires I explained to them how they all wore down differently, and I hate to do it because they are nice Michelin latitude tours, then he right away tells me the ball joints are bad and an outer tie rod...so with the estimate of everything I walked away and no time to wait on all that for now til Saturday probably. An over $1300 estimate in new tires, outer tie rod, two ball joints, alignment...so all that bad crap with the alignment can't be done before those parts gets replaced....problem from day one with the awd crow hopping those parts needing replacement???? Wearing down my tires eh?Sound right folks???

Still on Tuesday I'm getting the front differential small leak looked at/fixed from pinion seal leaking....

So I started thinking....what if I just get the tie rod, ball joints and alignment done and tell them to put the two most identical threadware tires on the front end with the existing tires???? Maybe see if all that fixes my crow hopping??? What do you think??? It would save me over $600 on new tires!!!!

 

[Sparky]

I really don't think tires are going to cause crow hopping. I've been wrong before but that just doesn't seem right to me.

Ball joints and tie rod end can explain bad wear on the tires and should be fixed. But again, not going to cause crow hopping...

 

[Black_Bravada]

If the Bravada is the same suspension as the Trailvoys, then you don't need the 4 wheel alignment. We have no adjustments in the rears, some cars do actually.

I know the dealerships WILL charge you the 4 wheel alignment just because it's a truck and that they can.

I got into it with the guys at Belletire asking why they charging me more and why they cannot adjust caster and camber.
Now they know every time I go in, they know not to give me an estimation sheet for parts and labor and always charge me for a 2 wheel alignment.

BTW, what was the estimate to get that pinion seal replaced?

Alignment is going to cost $65...and I didn't know at the time so I said a 4 wheel alignment....$65 not bad right??? Probably just the front two...and I'll get estimate/fix on Tuesday for the pinion seal leaking...

 

[Black_Bravada]

I really don't think tires are going to cause crow hopping. I've been wrong before but that just doesn't seem right to me.

Ball joints and tie rod end can explain bad wear on the tires and should be fixed. But again, not going to cause crow hopping...

I don't know anymore...maybe just get tie rod, ball joints fixed and an alignment.... same thread ware on each axle???? See how it is??? I I don't know anymore...

Still gotta find time to lift up front end and spin the wheels see what happens...

 

[chief0299]

I know I'm new and all, but I'd like to throw in some things I've learned over the years. If the crow hopping is what I think it is... the front tires feeling choppy in turns... I used to get the same thing on the rear axle of a Dodge pickup I had after I put a solid locker in the rear. Every turn I'd take the rear end felt like it was hopping. With a limited slip gearbox, it would allow the axles to spin at a slightly different speed in turns. The locker wouldn't. I'd check your front end, as described, by getting the front wheels in the air and spinning them. They should spin in opposite direction of each other. I'm not familiar with the AWD set up on these vehicles and whether or not they come with limited slip gears or not. But I would imagine they do. You may have a gear/clutch problem in that differential. Again, I'm not familiar enough with the vehicle or axle to say for sure. The hopping could very well be coming from binding up in the transfer case.

As for your tires... worn out ball joints, control arms bushings and inner and outer tie rod ends will cause uneven tire wear. Unless you have a radial tire pull from the belts becoming used to the alignment being off, you can probably get away with not replacing them. Especially if you don't have the money to replace them right now. Have the auto shop do a shake down of the suspension and show you the excessive play in the components they reccomend replacing. A good mechanic/sales person should be willing to let you get hands on to feel the problem. When I ran a firestone franchise, that's how I did things. I would rather the customer see and feel the problem, rather than just taking my word for it. Most reputable shops will do a free alignment check or charge you a small amount for the check. That means putting it on the rack, putting the head sensors on the wheels and going through the entire set up. Unless they're using an antiquated Bear alignment computer, they should be able to give you a printout of where each setting is at and it will also tell you what the factory settings and limits are.

 

[Black_Bravada]

Just lifted up front end....they spin opposite ways!! I'm going to call my tire place tomorrow and say....I need those ball joints and left tie rod replaced and rotate tires and alignment, most identical to the front.... fingers crossed!!! Everything else checks out good!!!

I really don't want to replace my nice Michelins with way cheaper Generals!!!!!

My current Michelin Latitude Tours are $250-$300/ea....new General Altimax $160/ea

 

[gmcman]

Can you post a pic of the tire tread? Sounds like they still have some life in them, mine went 70K easy. What inflation pressures are you running? Religious rotation is a necessity, otherwise you will pay twice as much for tires. $4-500 per tire will wake anyone up in the rotation department....that is if you never rotate them.

 

[v7guy]

It all sounds kinda sketchy to me. Being unable to get a concensus between these shops really makes me wonder. I think Chief brought up some valid points.

The way I see it, you got two options (assuming those parts are bad).
Rent the balljoint press (or buy the replacement control arms from mevotech, the replacements are a lot easier as far as work load) and swap em out yourself along with the tie rods and then take it to get aligned and go from there.
Or you can trust the shop and pay the 1300. The parts, depending on what you go with, are somewhere between a third to half the price they quoted you.

 

[Black_Bravada]

Can you post a pic of the tire tread? Sounds like they still have some life in them, mine went 70K easy. What inflation pressures are you running? Religious rotation is a necessity, otherwise you will pay twice as much for tires. $4-500 per tire will wake anyone up in the rotation department....that is if you never rotate them.

Well I keep all my tires at 32psi cold, and check religiously, and I went ahead and got new tires, outer tie rod, two lower ball joints, and alignment.....and went for a long time no more crow hopping!!! But still noticed it felt like the 4 wheels got a lil tight and hard to turn into a parking spots...just no hopping at all even at crazy McDonalds drive thrus.... so I was reading about how you can possibly end up having bought a new t-case motor that burns out/ goes bad quick...(second one I bought) first one was off eBay "new-open box" (i used in winter when awd did NOTHING, bought that fixed the awd problem then), so I went and bought this time from RockAuto.com...another motor....and boom!!! Perfect ride....freely glides into parking spots, slow tight turns etc.....no way of testing awd right now tho I guess...

I kept my old Michelin Latitude Tour 255/60/17....the two that were on front the thread read 10/32nds and the rears read 8/32nds.....and looking at them it really looks like the rears wore down pretty flat...so more of the tire was on the road, whereas the fronts look great still a nicer rounded look...and at 10/32nds (never myself used a tape to measure around the whole tire yet)...

So yeah besides all that money I put in it, I still gotta take it in sometime to get the front differential pinion seal fixed, very small leak, keeping a close eye on it, top off if/when needed....

Edit: about the old tires yours going 70k....I bought my Bravada 1 year ago..and maybe never been rotated probably every 6k....trust me I now am going to be on top of all that!!! And differential fluid changing, t-case fluid changing etc.....just really wishing I would've got a Trailblazer LTZ instead, I hate not being in control of the 4wd!!!!! Now I know.....

 

[Black_Bravada]

......who wants to buy some nice used Michelin's 255/60/17??? Lol...just don't put them on a Bravada!!!

 

[DrRansom442]

I got a quote from a shop here in the St Louis area for $125. - $150 parts and labor to do the pinion seal .... thought I'd add that since it was asked earlier.

 

[Black_Bravada]

I got a quote from a shop here in the St Louis area for $125. - $150 parts and labor to do the pinion seal .... thought I'd add that since it was asked earlier.

Really?? I got an estimate for almost $1,200 he also said the age of vehicle (02) and miles (150k) he highly recommends replacing some bearing/s or shaft or something, says the 02 bravadas have the diff. Case in the oil pan???? That sound right???? I have a small leak....mainly (by 2 mechanics) said it was a pinion seal leak???? I don't wanna get ripped off, but still wanna do what's best! I plan on taking this truck to 200k+ plus miles....

And 10.8 labor hours!!!!

 

[Wooluf1952]

Really?? I got an estimate for almost $1,200 he also said the age of vehicle (02) and miles (150k) he highly recommends replacing some bearing/s or shaft or something, says the 02 bravadas have the diff. Case in the oil pan???? That sound right???? I have a small leak....mainly (by 2 mechanics) said it was a pinion seal leak???? I don't wanna get ripped off, but still wanna do what's best! I plan on taking this truck to 200k+ plus miles....

And 10.8 labor hours!!!!

No. The front diff is bolted to the side of the oil pan Drivers side) and goes thru a hole. Not actually in the oil pan. All GM 360's and 370's are like that.

 

[seanpooh]

Really?? I got an estimate for almost $1,200 he also said the age of vehicle (02) and miles (150k) he highly recommends replacing some bearing/s or shaft or something, says the 02 bravadas have the diff. Case in the oil pan???? That sound right???? I have a small leak....mainly (by 2 mechanics) said it was a pinion seal leak???? I don't wanna get ripped off, but still wanna do what's best! I plan on taking this truck to 200k+ plus miles....

And 10.8 labor hours!!!!

Same here, the dealership thinks they know everything

They too also quoted me over $1K because "we have to drop the oil pan and remove the front diff." I know thats a lie and they want more labor time to charge since the service manual found here you don't have to do any of that. All there is to do is drop the power steering crossmember to get more room to fit the proper tools and pullers.

 

[Mooseman]

Really?? I got an estimate for almost $1,200 he also said the age of vehicle (02) and miles (150k) he highly recommends replacing some bearing/s or shaft or something, says the 02 bravadas have the diff. Case in the oil pan???? That sound right???? I have a small leak....mainly (by 2 mechanics) said it was a pinion seal leak???? I don't wanna get ripped off, but still wanna do what's best! I plan on taking this truck to 200k+ plus miles....

And 10.8 labor hours!!!!

Unless the diff was run dry, I wouldn't worry about the bearings or anything else in there. As for the axle seals, unless there is visible leakage, don't worry about them until they do leak. The pinion seal can be done separately from the axle seals. Just have the pinion seal done and keep your money. And the diff can stay attached to the side of the oil pan as explained above. Whoever says that it needs to come out is trying to fleece you