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1998 GMC Sierra -- New Transmission

So I recently inherited a 4 wheel drive 1998 GMC Sierra. It was a lot nicer than my truck, and free so I kept the Sierra and sold my older truck. Looks like this may have been a mistake. The Sierra has 140,000 miles on it. And what I didn’t think about at the time is that a lot of the miles were work miles. It was used to tow equipment fairly often.

I’ve only had the truck for about 5 months now, I already spent about $500 to repair the A/C and now the transmission needs to be either completely rebuilt or replaced. Local area estimates are coming out to about $2000 give or take for the transmission.

I’m told that when the transmission goes that the engine usually isn’t far behind, and also that needing a new transmission at 140,000 miles is somewhat unusual and not a good sign.

What I’m wondering here is whether it’s worth putting the 2 grand in it, or should I sell it off and buy a used car.

I really don’t want to just keep putting excessive amounts of money into a 12 year old car.

So what are the odds that this truck is just going to be a money pit–would you sell it for what you could get and just pick up a newer used car?

For starters if you reported what the transmission is actually doing (and not doing) and gave some specifics from whatever shop did the estimates regarding the specific diagnosis folks might be able to say whether or not the need for an overhaul seems plausible. What kind of shop did the diagnosis? Did they provide you with any error codes that have been stored in the computer? What else do they know about what is not working correctly? Given any sign of a transmission problem a lot of shops will just say to rebuild it rather than to risk tinkering with an older, high mileage transmission.

That said, it wouldn’t be odd if it needed an overhaul given the mileage and history of towing - its not unusual and not a sign of anything. It certainly tells you pretty much nothing about the engine. If you want to know about the engine check the compression.

You should also keep things in perspective. You have a 4wd pickup truck with only 140K miles on it that you’ve now paid $500 for. Another $2000 only puts you to $2500. That’s not much.

At the same time, at this mileage anything could actually go wrong and you should expect to regularly put some money into it. But compare that to the payments & higher insurance premiums you’d be making on something that was newer with lower miles.

What you need is just a good local mechanic or mechanic friend who can go over the truck and figure out what kinds of things seem to be looming (brakes, tires, suspension…?) There are no certainties but there are ways of identifying the money pits.

As far as the actual symptoms, just yesterday the truck started stuttering at low speeds when shifting into second gear. At highway speeds I could feel (and hear) the transmission constantly shifting up and down (very loudly) while the RPM’s would rev up really high and the truck would slow down and then the rpms would drop and the truck would lurch forward. I parked the vehicle at work and checked the transmission fluid which was full. Went into work – came back out 8 hours later to find that reverse no longer worked. As in I can put it in reverse and the engine will just rev up with no movement.

I took the vehicle to AAMCO because the shop I frequently use is about 50 miles away (moved a few months ago) and I haven’t found a new shop yet. I don’t know that much about cars but they told me that they needed to do a “soft seal” replace the “bands and gears” and replace the torque converter at the least. They wanted $2200 to “rebuild” the transmission.

I called the shop I trust and let them know what was going on – they said that given the symptoms and what AAMCO said that I probably do need a rebuild or a replacement of the transmission, but that $2200 was far too much for a rebuild and they shopped around and said they can put in a remanufactured transmission in for about $1900 give or take with a 3 year 100,000 mile warranty.

I can limp the truck to the other shop, and have them do a full inspection and give me their thoughts. I really just hate to be putting this kind of money into the truck. Especially if I wind up needing to overhaul the engine 6 months down the road.

There’s just no reason to assume that the transmission having problems means that the engine is right behind it. How does it run? Does it burn any oil? Do you know whether or not it was reasonably maintained? Take it to a local shop and ask them to check it out - a basic compression check is very routine and will tell you if there are serious problems.

I would check the compression and if it checked out limp it to your old shop. Whoever told you that a transmission going at 140K was a “bad sign” (except for the obvious) and that the engine is normally not far behind is making stuff up.