Air bubbles in tranny fluid, Jeep, 1997 GC

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niero

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Now that you mention it the check engine light did come on about a week ago. Maybe I'll have the shop take a look at the crank position sensor, just to be sure. Thanks. The grinding was only when I shifted into reverse. I could have still been coasting very slightly when shifting. But I was able to drive into the parking space in reverse, and drive out of the space in Drive. The grind sound was similar to a stick shift when you don't quite make it into the right gear. To be safe, I just had it towed to the tranny shop. Speaking of stick shifts, how is it they don't wear out easily, considering how many times a person doesn't hit the next gear and you hear the grinding/whine? You never hear that noise with automatic transmissions.
 
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niero

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So, the tranny shop is saying the transmission is shot, and needs to be rebuilt. These guys have a good reputation, so I don't think they're lying. But it will be at least $2600, probably $3500. I might, MIGHT, be able to scrape enough money together. Advice? I've put so much into the Jeep the past 3 years, but I'm starting to wonder if I should cut my losses.
 
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Originally Posted By: niero
So, the tranny shop is saying the transmission is shot, and needs to be rebuilt. These guys have a good reputation, so I don't think they're lying. But it will be at least $2600, probably $3500. I might, MIGHT, be able to scrape enough money together. Advice? I've put so much into the Jeep the past 3 years, but I'm starting to wonder if I should cut my losses.
I vote cut your losses. I wouldn't put thousands into an 18 year old jeep. your main seals could go next.
 

niero

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Okay, I thought that sounded pretty high. I noticed a few things that didn't quite make sense. They weren't able to recreate the problem (the grind) - though since it was rush hour, they'd only tried by driving around the parking lot, and shifting in and out of R & D. I then asked to do a filter/fluid change, but not to suction. Needed it anyway, but to let me know if they see anything. Shop called back, said there was more metal than usual in the pan around the magnet, which indicated more wear on components. That, coupled with the air bubbles on the dipstick (they said they didn't know what would cause that until they took it apart) indicated that it should really be taken apart, replace worn parts. I asked them to just change the fluid & filter, and I'd have to go with that. I'm going to get a second opinion. If I understand correctly, any old transmission will have metal in the pan on the magnet, and watching youtube vids on how to do fluid change on an AT, there was a fair amount in most of the Jeeps, but the tranny's were still good. In a rear diff you're going to see shavings, but that's natural. Isn't it the same w/ transmissions? Thanks all.
 
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My ATF magnet had a decent amount of crud on it with about 45k. If you're unsure of its service history, an abnormal amount of crud doesnt sound too unreasonable. This could also be the shop over exaggerating too. shrug Have you gotten the Jeep back and if so, how does it drive? How many miles does it have anyways?
 
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I had the air bubbles like that before. Iong story short, You have a loose valve body to case or a bolt fell out that holds valebody to case. hydralic leak make the bubbles. These trans are real similar to a old tf727.
 
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Originally Posted By: Highline9
I had the air bubbles like that before. Iong story short, You have a loose valve body to case or a bolt fell out that holds valebody to case. hydralic leak make the bubbles. These trans are real similar to a old tf727.
Changing the fluid isn't going to fix this.
 
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If you decide to drop pan check ALL bolt that have valve body together adjust bands. I would change out these parts as well they control line pressure.http://www.ebay.com/itm/like/200919005918?lpid=82&chn=ps
 
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The governor solenoid and pressure sensor have o ring that can fail. This will cause the bubble in fluid and lose line pressure. It sounds like you didn't drive much when trans not running right. The chances are your trans is fine. those repair shops know how east it is to rebuild a 42re and drain your pocket. The are not a bad trans. These trans need a little tuning on valve body and a line pressure raised.
 

niero

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Originally Posted By: dlundblad
My ATF magnet had a decent amount of crud on it with about 45k. If you're unsure of its service history, an abnormal amount of crud doesnt sound too unreasonable. This could also be the shop over exaggerating too. shrug Have you gotten the Jeep back and if so, how does it drive? How many miles does it have anyways?
Okay, that's good to hear you had the same thing. It feels like the tranny shop was overemphasizing the wear/possible damage, at least a little. The tranny has 221,800 miles on it, so by the sound of it, I don't think the shavings were as severe as I thought for that amount of miles. I had them change the fluid and filter. Confirmed that they put in ATF+4. I talked to them a while several times, and they didn't mention anything about missing bolts. Where is the valve body? Turns out the fluid was actually about a quart and a half low, not high. They had 4 different guys drive it before the fluid change, trying to get it to act up or grind. They could not get it to misbehave. Sluggish shifting, but they said it responds exactly how you would expect a high mileage trans to respond. Only issue they could find was the extra shavings on the magnet. I checked the fluid, no bubbles. Will check again today or tomorrow. It drives just fine, exactly like it always does. So I'm hoping it's okay and I don't need a new trans. But I've at least determined that if needed, I'm not rebuilding it, I'll just put in a used one. Thank you for the replies.
 
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Just to add my own experience to what has been said already: My "terrible" 1996 42RE has 254K miles on it. In my experience, a cooler line fluid exchange of ATF+4, a fresh filter, a band adjustment as well as a line pressure increase works wonders for performance and longevity. Adding a good stacked plate cooler for good measure can't hurt either. Our Jeep shifts flawlessly with no signs of giving up anytime soon. I attribute it to 50K ATF+4 fluid and filter changes along with band adjustments, line pressure adjustment increase as well as the cooler that I added. The governor pressure solenoid and sensor have never been replaced. In your case, I would at least get a shop to adjust the bands (if they didn't already) as that is a normal maintenance item on these and that should firm up/speed up the shifts if they have never been adjusted before. Here is the spec that I have used on mine that a high performance transmission shop recommended for the 42RE online some years back: Front band (on driver's side of case) Loosen lock nut; tighten adjuster (square head - tight clearance to reach) to 72 INCH pounds or snug and back off adjuster 3 turns. Hold adjuster steady and tighten locknut firmly. Rear band (adjuster inside pan on low-reverse band lever - hex head on adjuster if I remember correctly) Loosen lock nut; tighten adjuster to 72 INCH pounds or snug and back off adjuster 3 and 1/2 turns. Hold adjuster steady and tighten locknut firmly. Line pressure adjusting screw: Drop the pan, look on the drivers side for a small plate with an allen screw with a spring behind it (the head of the screw will be facing toward the drivers side of the truck also) Mark the screw with a scribe or paint for easy visibility when turning it (will probably need to use small needle nose vice grips due to clearance issues). Turn the screw out (CCW) 1 and 1/2 turns but no more the 2 turns or it may set off a MIL light on the dash. Note: This adjustment does NOT need to be adjusted every time the bands are adjusted. I would only change this adjustment once.) Best wishes with your transmission. Andrew S.
 
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