[Don Chapman]

My job location recently changed so im looking for a more fuel efficient vehicle than my f-350 crew cab. 14-15 mpg. I dont like small cars so im looking into used Bonnevilles
Ive heard they get 25-30mpg hwy with the 3.8ltr engine. Im sure thats got to be pretty close but wanted to hear from those who have actually have one. Also any info on reliability would be appreciated. Thanks,Don

[mike nixon]

That should be close. My 98 will run 28-30 on the hwy.

MIke

[67drake]

I just sold my 98' Lumina with a 3.8. I would get 29-31 on the highway if a drove @ 60-65 MPH.
The only problem I had was an intake manifold coolant leak @ about 150,000 miles. I sold the car with almost 170,000 on it and it's still going strong. I sold it to a daughter of a guy I work with,so he would let me know if she had any problems with it.

[Don Chapman]

Ill probably be looking at high mileage ones since its just a second vehicle and dont want to spend much. Did run into a 2001 Bonny yesterday for 2000.00 but high miles 193000. Looked to be in good condition but have not talked to the guy yet. One of his
employees said it was a company car and drove it mostly on the highway. High miles dont really scare me like some if they are highway miles.

[se428bandit]

You should be able to get 29-30 mpg on the highway.My '93 Bonneville would get 31 on the highway when i would go to floriduh to visit the folks.Only problem i know of on those cars in the plastic intake gasket.

[IOWA552SLOW]

Had a 99 bonni for awhile pulled high twentys with no problems. have had several gm cars with the 3800 motor all seamed to average in the high twentys to low 30s on the highway. my bonni had 170,000 miles when i got rid of it. the wife's current impala has the 3800 and averaged28-29 mpg last time we took it down the interstate at 70-75 mph. just watch the intake and overall flow tank for signs of a coolant leak.

[67drake]

I sold mine with 170K,I got $1500 for it.
I will add that this car drove GREAT still ,smooth as silk going down the road,not even any wind noise,squeaks or rattles after 12 years.
I only sold it because we had 7 cars/trucks in the driveway,and it was just in the way.

[Half-Inch Stud]

Our 3.8L Buik had one of them Computer-"Check-Engine" Stall-out on the highway options.
Had to get the Junkyard 3.8L computer and that ghost is gone.

That 3.8L Buick has gone through Coils and individual plugwires.
But when all the sparks are working it pulls hard and is real smooth on the highway.

[RS72LEMANS]

You guys are forgetting the oil pan gaskets leaking and the engine mounts failing due to being covered in oil. 2001 monte gets 31-34 highway. Great engines if you can keep up on the leaks. Im pushing that 280000 mile mark this month.

[Don Chapman]

Originally Posted by 67drake

I sold mine with 170K,I got $1500 for it.
I will add that this car drove GREAT still ,smooth as silk going down the road,not even any wind noise,squeaks or rattles after 12 years.
I only sold it because we had 7 cars/trucks in the driveway,and it was just in the way.

Thats good info 67Drake I would think a Bonny is worth slightly more than a Lumina and its 3 years newer than the one you sold versus the 1 im lookin at. I was kinda surprised
when I walked up and looked at the Bonneville and the sign said 2K or offer. I expected it to be rough for that money but the paint and body were real nice. Could only find one
1/2 dinger on the trunk lid and some slight surface rust starting on the top of the driver side rear wheelwell (im sure its a sign of things to come).Looks Ill be taking a closer look monday if its still available. Its an SLE model too.

[67drake]

No problem.
Yes,I would think your Bonne would be worth a little more,just trying to throw a close comparison out there for you.
The only complaint I had on mine was the brakes. I would think the bonne would be similar. I always get my parts from NAPA and even their middle of the road pads and rotors would seem to wear quickly,and I ended up with a few warped rotors.
The last brake job I did I told NAPA to give me the best pads and rotors they had. Pads were about $110 and rotors around $65 each,IIRC. These were still in great shape when I sold the car,and had about 20K miles on them.

[Don Chapman]

RS72Lemans that pretty impressive 280,000 miles. Thanks for the info on the leaks.

[Stuckinda60s]

I've had 3-3.8's, A '92 Bonneville I rolled at 94k miles, a '97 GP I ran to 140k and an '04 GP I only had for 30k. None of them used any oil, not needing oil when I changed it at 12k miles, or 12-months. That's how often I changed with Mobil-1.

My daughter has two Bonnevilles, one '95 SSE with 270k on it and a '95 SSEI with 140k on it. She has the oil changed at 3-5k. The supercharger in the SSEI just went and needs to be replaced and the SSE had the manifold issue at 190k, but they're both still good cars. She bought the first Bonneville with 50k on it to replace an '89 T'bird, 3.8, that was a piece of junk at 75k. Even though it had been babied all its life. It was a dealer's daughter's car and had 20k on it when Colleen bought it.

I wouldn't hesitate to buy anything after '92, if it was in good shape. I've heard the years with the manifold issue are '94 through '04. If I hadn't rolled my '92, I'd probably still have it. It still looked and drove like new, after 6-years.

[Don Chapman]

Thanks to everyone for responding on the mileage and reliability on the 3.8L.
I took a 2001 Bonny with 193k on it for test drive today. ran smooth, idles quiet, no smoke, plenty of power. Car has a couple of issues. Service engine light is on. A/c no worky. Car seemed to shake when braking on the off ramp from the highway. was fine when going straight. Overall seems like a good car for the asking price of 2k. I think i can get it for less if I decide to get it. Needs a good detailing. Tires 50% left on front more on rear, (Mich X green). Service engine light a big deal? Im guessing a sensor or something?

[Lightfoot]

I drove a '96 SE for a year. It did 30-31mpg on the interstate. The normally aspirated 3800s all get that kind of mileage when kept under 75mph. Super charged versions struggle to get over 28.
Try browsing this forum for possible answers to the SES light:
http://www.pontiacbonnevilleclub.com/forum/index.php

Could be as simple as the gas cap not tightened properly.
Those Michelin tires will last a long time if you keep 'em rotated.

[Don Chapman]

Well I got caught snoozing on this one. Called the guy back and he just sold it.
Have feeling I wont be finding another one like that for any time soon for 2k.
I just started looking into something more fuel efficient a few days ago and did not
realize what a good deal it was. I checked kelley blue book value and even in fair condition booked for just over 3k with the options it had. The guy had the kbb sheet on the window but must not have had all the options entered as his showed 2,395 or so as the value. You guys have all been great about the questions Ive had on the Bonnevillles. It will help in choosing when I find another. Been looking at Buick Lesabres
too but they seem so boring. Bonnevilles seem so much sportyer. May consider a smaller Grand Am or Grand Prix. Thanks, Don.

[PMDJIM]

Don, if your going to look at Grand Am's or Grand Prix's I'd stick with the GP's. Grand Am sixes do not get the same gas mileage as the 3.8. Grand Am 4 cyl. do ok but it's a 4 cylinder.

[60man]

I presently drive a 2003 Bonni with Gen II 3.8L. Just turned over 104,000 mies. I love this "little" car. It's pretty well loaded with leather and all the goodies and gets about 25-26 MPG in congested suburban driving. On open road 29-31 is the norm. I have no oil leaks nor water leaks. Only complaint is electric window regulators ....two in 5 years. But I had same problem with my 2000 Buick LeSaber..it also did great on fuel. Both cars are/were solid and peppy.
I lost my 2000 Buick to a rear end collishion by a kid texting or I would still be driving it !..
Oh yeah....goes good in snow..

[pontiac6269]

My 98 Olds 88 just rolled 233,000, runs and drives great. Would prefer a Bonneville or a GP as I like the firmer suspension. It gets 28 - 30 mpg on the highway. I've changed the plastic upper intake manifold with one that has a metal sleeve where the EGR passage is and the lower intake manifold gaskets with the updated GM aluminum gaskets. Doesn't leak or use oil between 3000 mile oil changes.

[Stuckinda60s]

Quite some time ago, I posted that my '93 Bonneville would pull down 31-33 on a trip and a couple of guys pooh-poohed that. It was surprising how many guys jumped in to that thread and posted similar mileage.