Greetings all.
I may simply not be searching very well, but I have some questions about our new family wagon:

She is actually running pretty good. She starts right up (new starter), and rattles nicely down the road. Seems to have easily enough power (my wife was very impressed that she doesn't slow down on hills at all like her old Jeep Cherokee did). Doesn't overheat. Uses about 1 quart of oil in 3000 miles, which is how often I change the oil (Rotella T 15W/40 Fram filter).

However, there is a horrible rattling noise beyond the standard rattling of the diesel. Listening with a hose pinpoints it to the turbo. pulling the intake hose off the turbo and playing with the shaft, there is a small amount of play up and down, and none in and out. How bad is that? Which turbo is it? The number plate up top is useless. I cleaned it off, and it still doesn't say anything like GM-8 or GM-4. The numbers around the bottom are 51T/32 0774N 2. the 0774N is on a plate. There was a turbo unit on Evilbay, with 51T/32 0694N 6 for numbers. Would that have worked?
There is also a more quiet rattling at the valve cover right next to the turbo. If you move away from the turbo, the sound goes away. it's only right next to the turbo.

I also had an issue wherein on a 4 hour drive at night, the headlights would dim, and the battery gauge would start going down. Then, when it got down really low, it would kick back on. most of the time. one time it didn't and I had to pull over and restart the truck, and then it came back. The alternator tests good with my tester. It has one new battery, and one old battery that likewise tests good. It also refuses to repeat the problem now that it's only driving locally, even if I drive it the same 30-50 miles I had to do to get it to have the problem before. My gut says regulator, but my gut is wrong way too often to trust.

It also has a leak somewhere in the power steering system. There's way too much oil all over things to find it easily. What is the recommended way of cleaning these things? Someone told me not to use water or spray it down as the diesel's systems get tempermental when they get wet.

I'm sure there'll be more questions to come.

Thank you
John

Welcome to "The Place!" Remeber to fill out your sig. If the turbo is stock, it's a GM-4.

Start by checking all electrical connections on the alt., batteries (remove and insepct connections at batteries) and grounds on the block.

I've hosed my engine down with no issues.

Welcome to "The Place!" Remeber to fill out your sig. If the turbo is stock, it's a GM-4.

So, does this mean that the extra rattling it is making does in fact mean that a replacement turbo is in my not-very-far-distant future?

Start by checking all electrical connections on the alt., batteries (remove and insepct connections at batteries) and grounds on the block.


I've hosed my engine down with no issues.

I did forget that before the problem went away, I pulled all the battery connections from the old battery and sanded them down before putting them back. since then, it hasn't had an issue, but again, it hasn't had a long trip.

the heat shield on uor turbos are known for rattling put your hand on it WHEN ITS COLD and see if the sound clears or changes id check that before replacing

the heat shield on uor turbos are known for rattling put your hand on it WHEN ITS COLD and see if the sound clears or changes id check that before replacing

Thank you. I'll try that.

the heat shield on uor turbos are known for rattling put your hand on it WHEN ITS COLD and see if the sound clears or changes id check that before replacing

Ok.. I tried that out. no change.
Anything else I can try? I'd rather not replace it. If I did replace it, I'm told I have a GM-4. Would a GM-6 or GM-8 fit? What's the difference?

sigh.
all I need now is (maybe) a turbo, (maybe) an AC compressor, (maybe) a hydroboost, (maybe) an alternator, and definitely an expansion valve, and then I think she'll be good to go. :-)

GM-8 will go right on.

GM-8 will go right on.

What's the difference? What will it change? the engine has 213K miles on it, and this is the supposed to be the family reliable vehicle, so I'm not sure if I want to add too much performance stuff that might make other parts go bad.

that said, she only gets 14MPG. Anything that will increase that has got my vote, as long as it won't kill the truck! :)

GM-8 is a bit more efficient, supposedly spools quicker, and the wastegate is verticle instead of horizontal.

Might wanna check injectors. With your milage, if they're factory, they should be replaced. Could cause your milage problem.

Might wanna check injectors. With your milage, if they're factory, they should be replaced. Could cause your milage problem.

yuk.
I had thought that 14MPG in town was pretty close to standard for the ~4.10:1 'burbs?
that said, I know that on all my older cars, they start off getting 15MPG, but with some help, I can get them up over 17MPG. I just figured there ought to be a way to get better than stock mileage out of the 'burb. Ideally, if there's a part to be replaced, and an upgrade will help with that, then the upgrade's the way to go. i.e. if the GM-8 will work better than the GM-4 that it came with, and increase the mileage a little, then I'd rather get that, all other things being equal.

It's not like she seems to be lacking power. She's the only thing I've got that doesn't have to drop into passing gear on the grade out of the valley.

You want better mileage, go veggy.

Frybrid is the best solution for 6.5's and especially Suburbans.

Good luck to you.

yuk.
I had thought that 14MPG in town was pretty close to standard for the ~4.10:1 'burbs?


Yep. 14MPG sounds about right with 4.10's. I'm lucky to get that with my pickup.

It may be your exhast system. Mine rattles. The rubber bushings that connect the exhaust to the body get worn out and start to sag. Mine bangs on a cross member.

When cold I would get up under the truck and start shaking the exhaust (hard) in different places to see if it bangs on anything.

Well, yes, 4.10's, that seems to be about average.

that said, she only gets 14MPG. Anything that will increase that has got my vote, as long as it won't kill the truck! :)

Do you have the stock exhaust?

Do you have the stock exhaust?

I do. Eventually, when I'm rich, I may go to a 4" exhaust. I was thinking of starting with a better air filter setup first though.
And that's after fixing the AC, figuring out what the extra rattling is that sounds like it's at the turbo, and fixing the power steering fluid leak.

Pull the drive belt, check the vacuum pump, alt., PS pump, have a look at the harmonic balancer as well.
Try running without the belt any quieter?

On my '94, I had a slight rattle for a while...I initially suspected turbo, but after a month or 2 of driving it around, the A/C Compressor pulley bearings were shot...rather than spring the expense of a reman compressor, I went to AutoZone and bought just the bearings...the pulley requires a special tool to remove, and I couldn't find one...I went to one of the local garages and the guy popped it off in like 30 seconds. The whole ordeal cost me like 20 bucks, I think. I'd pull the belt off and check that pulley before assuming the turbo is bad...just don't ignore it like I did...had I checked the pulley bearings sooner, I would still have A/C...now, the clutch is fried, and I need a new compressor...usually when the turbo bearings are bad, there will be a lot of play in the turbo shaft...as long as it spins free and the fins don't hit the turbo housing...USUALLY, the turbo is fine...

Other suspects...the clam-shell clamp on the bottom of the turbo housing that holds the down pipe on...maybe the heater hose that goes across the block between the valve cover and the intake manifold (check to make sure it's not tapping on the intake or valve cover)

Don't get frusterated...the guys here are great at helping figure stuff like this out. Be PATIENT and Continue to check the things recommended to you, and don't jump to conclusions. From the sounds of it, you have a pretty good running 'burban to haul the wife and kids around...take care of it, and it very well may last a LONG while. The key to owning one of these trucks is just that...taking care of it...

While you are down there...check your downpipe...is it smooth or all crimped up?? If it's the stock downpipe, you should buy a downpipe and crossover and replace it. The stock ones are HORRIBLE, and some of them you can't even drop a golf ball through. This will cause your EGT's to skyrocket under heavy acceleration, ultimately leaving you with cracks all over your heads...from there, delete your cat at least...with that many miles, it's likely it's plugged up and doing you more harm than good. I used the original exhaust flange and welded a piece of 4" straight pipe to it...much cheaper than buying a system, and the turbo quiets it down enough for my liking...In a burban, though, I'd put a muffler on it, I think...

As far as mileage goes...it sounds like your gears are what's hurting you the most...I'd swap a set of 3.73's into it if thats not out of the budget...I dunno about the 'burban, but my pick-up gets 18-20 mpg with 3.73s in it. A free flowing exhaust will help too, along with making sure your air intake is free and has a clean filter in it.

On my '94, I had a slight rattle for a while...I initially suspected turbo, but after a month or 2 of driving it around, the A/C Compressor pulley bearings were shot...rather than spring the expense of a reman compressor, I went to AutoZone and bought just the bearings...the pulley requires a special tool to remove, and I couldn't find one...I went to one of the local garages and the guy popped it off in like 30 seconds. The whole ordeal cost me like 20 bucks, I think. I'd pull the belt off and check that pulley before assuming the turbo is bad...just don't ignore it like I did...had I checked the pulley bearings sooner, I would still have A/C...now, the clutch is fried, and I need a new compressor...usually when the turbo bearings are bad, there will be a lot of play in the turbo shaft...as long as it spins free and the fins don't hit the turbo housing...USUALLY, the turbo is fine...

<snip>
As far as mileage goes...it sounds like your gears are what's hurting you the most...I'd swap a set of 3.73's into it if thats not out of the budget...I dunno about the 'burban, but my pick-up gets 18-20 mpg with 3.73s in it. A free flowing exhaust will help too, along with making sure your air intake is free and has a clean filter in it.

That may well be it. the AC is definitely having trouble and was high on my list of stuff, but I considered a turbo to be higher priority if bad. The AC unit does make a great deal of noise. I'll have to try that. Is it hard to do the bearings?
I know that one of my buddies who used to do AC said that he didn't consider it worth it on these to rebuild them.

Also, while on the subject of AC, anyone have any idea why it is that I can't get the 134 charge hose to work? The 'burb is definitely 134. The fittings are the 134 fitting style, but I cannot get the charge hose attachment to connect fully, so I get more stuff out of the lines than I get in. I was trying to put some lube in it to help the compressor last a bit longer. Do these fittings go bad or something? the fittings are very similar to quick connect fittings on an air compressor, but no matter how hard I push, I can't get it to lock in.

Believe me, this has become THE site I check every day now. The folks on here are incredibly knowledgeable, and manage to pass it along without making me feel like a dolt. It is much appreciated.

4" downpipes and stuff like that are in the upgrade section of things. I hope to have this 'burb running for many years to come. First, I have to fix the broken stuff (with upgraded stuff where possible!), and then I can look at improvements. Air cleaner and exhaust seem to be the most prevalent, cheap, and bang for the buck upgrades.
I think I'd like to put together an intercooler system after that. someday. when I'm rich :-)

Thanks again
John

Those sounds that you are describing are very framiliar to what I am hearing in my truck. This occured just prior to my truck billowing white smoke, check my earlier post:
http://www.dieselplace.com/forum/showthread.php?t=176627

I just did a repair on the x-over pipe under the truck and then I started hearing turbo noise around 1500rpm and a knocking coming from the top pan just behind the turbo. Then the turbo noise increased to all rpms. Then I lost alot of power and I have HUGE white smoke problems. Now the guys are helping me to diagnose this problem in my truck, I haven't gotten a chance to do any checks yet but I'm going to check my turbo for play and internal oil leaks as soon as I get back home. I hope that you don't have my problem.

Those sounds that you are describing are very framiliar to what I am hearing in my truck. This occured just prior to my truck billowing white smoke, check my earlier post:
http://www.dieselplace.com/forum/showthread.php?t=176627

I just did a repair on the x-over pipe under the truck and then I started hearing turbo noise around 1500rpm and a knocking coming from the top pan just behind the turbo. Then the turbo noise increased to all rpms. Then I lost alot of power and I have HUGE white smoke problems. Now the guys are helping me to diagnose this problem in my truck, I haven't gotten a chance to do any checks yet but I'm going to check my turbo for play and internal oil leaks as soon as I get back home. I hope that you don't have my problem.

I certainly hope not too.
I'm not having any trouble with power or smoke. I don't even get a puff of black smoke when she's first starting off. I had a mechanic friend of mine listen to everything yesterday, and he's pretty convinced that the major cause of noise is the AC compressor. We're going to do some work on the rear AC unit as soon as I get the funds and I'll put some oil into the compressor and see if that helps.
I did check the turbo for play, but the play is negligible. I'm not sure how much is allowed, but it's less than can be measured with anything I have.

Best of luck with yours!
These guys seem to be pretty awesome and a veritable fount of knowledge.