'89 Suburban...lemon?

I hope I didn't just buy a lemon. I bought an '89 Suburban/350/700r4 with 160,000 miles a few months back and I am having a few problems with it. First, and most annoying is the awful mpg, about 8-10. I don't know much about vacum hoses but I know that they are suposed to lead somewhere and not just be cut off or missing as mine are. Might that be causine problems? And, if so, can I find a find a diagram somewhere? Next there are no "breathers" in valve covers. On the saftey side of things, I will be driving anywhere between 15-40m/h and out of the blue the whole truck begins to shake violently. It feels like the whole thing will fall apart and I have to pul to the side and slow to 5m/h. It will them stop and will drive normally for a while untill it comes from nowhere again. I never know when it will happen. Could this have something to do with a quarter turn of play in the steering wheel?(it's a b**** to keep on the road) I have many other problems of varying sizes that I'll get to later. Thanks for ANY advice as I can turn a wrench, and like to, but I have limited experience in repairs.
Joe

I hope I didn't just buy a lemon. I bought an '89 Suburban/350/700r4 with 160,000 miles a few months back and I am having a few problems with it. First, and most annoying is the awful mpg, about 8-10. I don't know much about vacum hoses but I know that they are suposed to lead somewhere and not just be cut off or missing as mine are. Might that be causine problems? And, if so, can I find a find a diagram somewhere? Next there are no "breathers" in valve covers. On the saftey side of things, I will be driving anywhere between 15-40m/h and out of the blue the whole truck begins to shake violently. It feels like the whole thing will fall apart and I have to pul to the side and slow to 5m/h. It will them stop and will drive normally for a while untill it comes from nowhere again. I never know when it will happen. Could this have something to do with a quarter turn of play in the steering wheel?(it's a b**** to keep on the road) I have many other problems of varying sizes that I'll get to later. Thanks for ANY advice as I can turn a wrench, and like to, but I have limited experience in repairs.
Joe

Joe: Unless you bought this vehicle at a "dealer" expect some problems. 1st lets go for the mileage. These vehicles ain't honda's!! They get 8-10 to upwards of 15 on the highway. The late 80's were particularly rough on gas mileage.

You should be able to take it to a Chevy dealer and give them the VIN and get a vacuum diagram. I did it about 12 years ago for my Bro in law's 84.

The play you have in the wheel is EXCESSIVE to say the least. Get it to a good alignment shop and have them at least check the alignment. Soundds like you got some loose tie rod ends, bad idler arm and a few other problems. If you can do the work on it, by all means do it. THEN take it back to the shop for an alignment.

As for experience, there's nothing like dirty fingernails, (and a grouchy wife when you use "HER SINK" to clean up!), so go down to the parts store and get a Chiltons/Haynes manual for your particular year Suburban. Read thru the procedures 1st, look at what you have to do and read it while doingit.

Hope this helps.

Larry

I hope I didn't just buy a lemon. I bought an '89 Suburban/350/700r4 with 160,000 miles a few months back and I am having a few problems with it. First, and most annoying is the awful mpg, about 8-10. I don't know much about vacum hoses but I know that they are suposed to lead somewhere and not just be cut off or missing as mine are. Might that be causine problems? And, if so, can I find a find a diagram somewhere? Next there are no "breathers" in valve covers. On the saftey side of things, I will be driving anywhere between 15-40m/h and out of the blue the whole truck begins to shake violently. It feels like the whole thing will fall apart and I have to pul to the side and slow to 5m/h. It will them stop and will drive normally for a while untill it comes from nowhere again. I never know when it will happen. Could this have something to do with a quarter turn of play in the steering wheel?(it's a b**** to keep on the road) I have many other problems of varying sizes that I'll get to later. Thanks for ANY advice as I can turn a wrench, and like to, but I have limited experience in repairs.
Joe

How can you consider this truck a lemon? "Lemons" are considered new vehicles with concerns that cannot be satisfied by the manufacture in the customers eyes.
You are the proud owner of a 15 year old vehicle with a questionable service history.
Fuel mileage...Suburban and fuel mileage do not go togather..with proper maintence and some "fuel mileage" improvements, you may get 12 out of it.
Your vibration and steering play is a steering problem caused by worn parts.
You need to have a certified tech take a look at this truck and determine if it is a safe vehicle.
My suggestion to anyone purchasing a used vehicle from a individual or a used car dealer is have it checked out by a trustworthy and certified technician.

GMMerlin is right on the money......
If you don't buy and sell cars for a living, pay the $100 to have it checked out. Its a lot cheaper than fixing it later. Dave

I did buy from a Chevy dealer and assumed(yeah I I know what they say) that a dealer would be obligated to give notice of major problems like these. Perhaps lemon was too stong a word....anyway, I should add that I am very happy with the consistant performance of the engine and transmission, except for the mpg and a very small puff of smoke on cold startups(bad valve seals?), both seem reliable. It is pretty quiet going down the road too, I'm going to have to try and fix that problem, I like a loud truck! Cold startups are better than any car I've had yet, and in minnesota it's pretty important. I was able to find a routing diagram and run new lines. I should be able to take care of the tie rods and a steering stablizer this week. I really appretiate the help and I'll let you know how it goes.

I bought an 88 with 350 33inch tires and a four inch lift. It has 143,000 miles and I get a solid 15mpg highway. It is well tuned and a real gem. I love this truck. I put 4 ounces marvel mystery oil in fuel per every 10 gallons. It increases mileage and keeps system clean. It also makes cold start up awesome. Of course I live in Arizona. Is it really cold here. I'm a desert rat and I think so, but it's not Minnesota. Try the Marvel Mystery Oil though it's great. I notice when I dont use it in fuel that early morning start up takes a bit more cranking. Good luck