Hi, this is my 1st post.In a couple of hours I'm buying a 1998 4X4 Suburban with 195,000 miles on it.The trans was rebuilt recently. In road use what important component/components are most likely to break and leave me on the side of the road? I 'm not concerned about power windows/seats/mirrors etc-just things that can strand me-motor,trans,rear end,ECM,alternator etc.
I would rather buy a lower mile vehicle, but $$ problems make this the best bet for what we need-a big  inexpensive($3500)vehicle to evacuate(New Orleans) 3 adults,2 dogs,4 cats, lotta stuff.It will also take me to work etc.I'm just wondering where to put any spare maintenance money other than the obvious-hoses, belts, lube,trans fluid etc.The alternator would be my guess, but maybe they last forever in Suburbans??
It occasionally will do some very very gently driving on beat up dirt roads paths, but nothing hard core.
Thanks,
Charlie  

You did not say if it was a 1500 or 2500 because that is a factor. VorTec 350's have a problem with intake manifold gaskets (coolant leakage). If it has never been replaced it is rare and it will need replacing one day. I would change lube is Tcase (if a 4x4) and drive axles now and get them at square one so to speak. Check coolant to see if it is clean and flush if need be and cooling system in general. (maybe replace water pump if it never has been replaced) Do change engine oil every 3K miles or so and DO NOT use 5w30 in a old engine like that especially in a warm climate (use 10w30). The 350 is a good motor and treat fairly good they can go 200 to 300K miles with ease. If engine is running good now and not using much oil, it is not going to die over night and will last a long time if you keep changing oil often. One more thing, I would stay away from 87 octane especially in warmer weather because it will reduce power and MPG. The knock sensor on engine does a good job of hiding your true octane needs and you will never hear it knock if it is working but you will see reduced performance and MPG.  

SNOMAN,
  Thanks for the reply.It is a 1500 (1/2 ton). The PO seemed like a pretty careful type guy.Before I test drove it he warned me at length about the Suburbans so so brakes(I had driven Suburbans before,they aren't terrible, just not good).He also cautioned me about what he said was"they can't be driven at high speed".I think his point was that it is softly suspended and has a fair amount of sway.I like a soft ride,and don't drive fast,so no problem.I suspect the shocks or struts of whatever it has are very old-any rubber/polyurethane bushing are probably original also.
My point is I think he took care of it-oil changes,trans fluid changes,coolant,diff lube etc.He probably did exactly what the manual suggested.
 Thanks for the tips on the intake manifold gasket.The motor is original;I'll call him and see if he remembers having it changed.I wonder if this is the engine and engine cooling knocks Consumer Reports blackballs the older Suburbans for(they give the 2004 on and the new 2007 good ratings-recommended)?Good to know-I bet that was the problem.I hadn't heard that the 350's had any engine problems,so I was surprised to see that in CR-BET IT IS THE GASKET.
 Do you see any advantage in using syn lube-75/140 in the rear diff? I had a Titan,and Nissan changed the lube specs because Titans eat differentials in normal-not towing-service.I sold it before having any problems; it was a fun truck-no problem for me.
No 5w30 huh!It is hot here-New Orleans,so 10w30 it is.
Thanks for the tips.
Charlie
PS I think I read a posting on mpg where you(or the guy you were arguing with) got spectacular mpg-15-16 in the city and >20 hy?? Wow-I expect 11 mpg city and maybe 17-18 hy.I'll  drop my teeth if I get over 14 city.You must be a pretty efficient driver.  

You might look in glove box at option codes for axle ratio. If it is a GU6 it is a 3.42 and not well suited for towing. If it is a GT4 it is a 3.73 which is a bit better. On the brakes, the Burb is a big heavy vehicle and the 1500 is built on a LD 1/2 ton chassis and brakes so it could have issues loaded if you stop hard. (the brakes on my 1500 have never been what I would call super) 3/4 ton burbs have much better brakes. On my MPG, it even amazes me sometimes how good it is on fuel. Engine is stock and I have advance stock baseline timing from TDC to 8 BTDC and I use 93 octane. Engine is VERY crisp is response and you basically breath on pedal a bit to get it moving out. It is in OD by 40 MPH 99% of the time and usually around 35 to 38 MPH. It is just a great engine/tranny/axle ratio/tire combo and it coasts really well too. I need 4 or 5 more years out of it until kids finish college. One more thing, on rear axle lube, you can use 75w140 if you want with no problems but you would likely get a fraction better MPG with 75w90. (I would use 75w140 SYN or 85w140 conventional if you plan to tow) In front axle it is best to use 80w90 as it has to do with the fact that front axle decouples through spider gear spin off and 80w90 minimum film thickness and 140 would increase power loss in diff in form of MPG.  

Thanks for the tips.1st thing I'll do is replace all the fluids/lubes-(transfer,differential,transmission,and oil).Then I'll do all the hoses and belt.This shouldn't be more than $100.
 How is the trans fluid usually changed? In the past I've drained 2 qts,then replaced 2 qts.I would do this about 3 times  -running it for a few minutes in between drainings.I have seen ads claiming that they can actually pump out all the fluid and replace it for ~$80.Do they really replace all the fluid when they do this?I always had my doubts about it since I do almost all maintenance myself.
I'll take your advice and use 80w90 in the front diff to get better mpg.I'll rarely actually engage the 4X4.I'll take the mpg penalty in the rear and use the 75w140 Syn in the rear since it might be "better"and oil is cheaper than metal.I'm guessing that the drain plugs are magnetic? Hope I don't find much metallic grunge on them.
 I will only be towing a really light-1500 lb loaded-Harbor Freight 4x8 cheapo trailer for evacuations(New Orleans).In the 2005 evacuation we had the Pilot SUV and a Titan pickup and they were both  fully loaded (we had two tall dogs-Phoebe and Isis greyhounds;4 cats,3 adults and a lotta "stuff").The Suburban has so much interior room we will be able to take just about as much stuff with one vehicles.It can't be beat for that.
Thanks,
Charlie  

I do fluid changes by removing pan (you need to to replace filter) and then topping it of with fresh oil (it takes around 4 or 5 quarts) While it is not a complete fluid change it does freshen it a good bit. Burbs are get people and freight haulers with lots of room in them. My 89 is even a bigger cargo box yet. Not to spend you money but I would suggest you get you a enclosed 5x8 trailer as it would protect content from weather and sticky fingers too and also let you preload it some if need be. A 5x8 (or even a 5x10) would add little extra aerodynamic drag and it would track in your wheel tread width and in a tight spot, anything burb cleared the trailer would clear too.  

Wow-the 89's have a bigger cargo area? I measured this one because I was wondering how much larger it is than our soon to be sold Honda Pilot(which is very wide-as wide as the Suburban- for a mid sized SUV).They are both about 49" between the wheelwells-and the spare that the Burb carries in the back. The Pilot is about 74" from the back hatch to the back of the front seats with the seats as far forward as a driver and front passenger could tolerate. The Burb is 97" back to the tilted up  second row seat(it will actually  flat carry  4x8 plywood/sheetrock-something most pickups won't do with their 6.5 beds).This space is just about dead flat; the space in the Pilot is tilted upward about 10 degrees,and I have to fill in(with plywood placed on the headrests) about 10" from the top of the 2nd row to the rear of the front seats.The largest 200+ inch minivans are a good 18" short of carrying 4x8 plywood.This Suburban has to be a do everything,haul everything and everyone vehicle.It is a gigantic minivan with tow capability.I'll keep my eyes pealed for a used enclosed trailer.It would be nice to have some security against thieves while sleeping at a rest stop.Open trailers put your stuff on display for thieves.
 If I pulled the 2nd row,and the 3rd it is 107" back to front. I would have to fill in with plywood, but that is no big deal.
 Thanks for the tips.
Charlie  

Once I carried a new 8 foot Fisher plow blade (and rest of mounting hardware and controls in back of it with no problem. Second seat is a 70/30 split so we folded on section  and slide plow in. It weighed close to 600 lbs but it carried it with ease along with 2 adults and 3 kids and luggage. I lived in MT at the time and nearest Fisher dealer was over 200 miles away so we had to drive to it to get parts. (plow was for another truck) The length of yours and mine inside is about the same but mine is more boxy and less rounded in corners and sides and it has a higher floor to ceiling clearance in it. Mine it not the smoothest ride either as it is more truck than car as it has 5 leafs and a booster on each side in rear and to takes loads really well for a 1500. Your do not want to run the tank dry as it hold 40 gallons but it is great on long trips and can go 500 miles plus without even thinking about as I have gone 600 miles and a bit more between fill several times. Typically it take 29 to 33 gallons when I finally fill it up on a trip.  

Boy, are you right about not running it dry.When I bought it , it was on E(fair enough since it only cost $2950, the owner didn't want to pay for my gas-he is a lawyer).I pulled into the gas station expecting a $75 fill up.I figured it had  roughly a 28 gallon tank like my Titan pickup. Well, when it got to 38 gallons I literally looked under the truck to see if there was a hole in the tank, or if it  was overflowing!! It finally clicked at 38.6 gallons-$111 and change!!!! Pulled out the owners manual-44 gallon tank!! I'll never run it to less than half full,especially if we have a hurricane, or some more grief comes out of the middle east,and we get $4 gas sometime soon(gas is $2.89 here,and apparently on the way up).
Thanks,
Charlie