Transmission Shot?

[yaktamer]

I know this is a little like asking for a medical diagnosis without seeing a doctor, but is this such a clear cut deal that the mechanics here can give a definitive yea or nay?

2006 Nissan Titan 4WD with 5-speed auto. 210K miles, original tranny. On hills at freeway speeds transmission appears to be "slipping" and tranny temp gauge is going way up. Also when heading downhill truck is downshifting as if tow mode is on when it is not. Any chance this is a repair rather than a replace situation?

 

[m1gunner]

Possible low line pressure problem.Slipping of the clutches causes "slipping" feeling and high temps. Cause is anything from clogged filter to stuck valve body spool valves, worn out pump, seals and clutch linings.

Does the tranny fluid look brown and have a burnt smell? If so, it needs a serious looksee and estimate for repair.

 

[PatriotX]

The 'going downhill' thing is unfamiliar to me and could be electronic in nature.

Without knowing the degree of slippage, it could be your TCC lockup not engaging or a toasted trans.

Does the fluid appear dark brown or have a burnt smell?

I would also opine that this is one of those sooner-is-better problems with regards to repairs. Good luck !

 

[PatriotX]

Lol, m1gunner beat me by a minute.

 

[yaktamer]

Thanks guys. This just started today. I was going to check the condition of the fluid when I got home to see if it was burnt but got sidetracked. I'll check it out in the a.m. Definitely something I won't wait to have checked out. Just trying to get a sense of whether I'm likely looking at having to dump the funds into replacing the whole tranny, in which case I might just trade her in rather than keep putting money into her given the mileage (though I hate the idea of having car payments).

 

[rwsmith]

Those two words are hated....

Transmission shot. I've had very little luck with getting them repaired and the expense is outrageous. The first one I took back to the repair shop three times before I got rid of the car. Every time I came out it had a new problem. Second time I went to the most reputable repair shop in town. They told me it was a bum transmission to start with, but that they could fix it, at great expense. When it went the second time about 6 months later I got rid of the car. There are a few less expensive parts and fixes like filters, modulators, bands, etc but if it gets into tearing one down, I feel like I'm better off getting rid of the car.

 

[msinc]

Hard to say...could be a simple repair, like a servo seal or band adjustment, but at that high mileage you are patching at best. No reputable repair shop is going to go in, find something simple {like a servo ring} just replace it and give it back "fixed." This is because of the high probability of something else going out in the near future and them now having a customer that believes they should be on the hook to fix it from now on. The way I see it you got two choices...new trans or new vehicle.

 

[m1gunner]

Hard to say...could be a simple repair, like a servo seal or band adjustment, but at that high mileage you are patching at best. No reputable repair shop is going to go in, find something simple {like a servo ring} just replace it and give it back "fixed." This is because of the high probability of something else going out in the near future and them now having a customer that believes they should be on the hook to fix it from now on. The way I see it you got two choices...new trans or new vehicle.

True.

Right out of college, I worked at a car dealership. The mechanics got paid little or nothing for a "quick fix" or minor adjustment. The guys that had bills to pay would go for the big jobs, rework the assembly and assure no "come-backs". Of course they would do the quick fix on their own cars (never buy a car that belonged to a mechanic), but rarely/never on a customer car.

Auto transmissions are big hydraulic pumps hooked to servo pistons to make them go. In a manual transmissions, springs hold pressure on the drive clutch. In auto transmissions, you have as "clutch pack", essentially a stack of small clutch discs inter-leafed with small pressure plates. They are jammed together with nothing but hydraulic pressure. If pressure is low, the clutches won't lock up, but continue to slip, and that quickly destroys the clutch linings (only slightly thicker than poster paper when new) and quickly overheats the transmission.

At that mileage, every shop will tell you it needs overhaul, without even dropping the pan. If It were mine, I would try changing the filter and fluid first. BUT, it may not even go at all if the old crud is the only thing keeping the seals from leaking worse than they are.

 

[msinc]

The other issue with those clutch packs, described above, is that they dont have a lot of play or lash when new. The hydraulic pressure that keeps them engaged from slipping has a pretty narrow range or movement. This means that when the paper thin clutch disks start to wear the additional "space" means less pressure to hold them engaged and this allows slippage. From high mileage wear you get slippage, from that you get heat. From all the above you get a lighter bank account!!!

 

[chaparrito]

You hear that sucking sound? It's the Auto-Tragic Transmission Black Hole and you are circling it's outer perimeter. Take your lumps and trade it off, or put it on Craigslist as a mechanics special. Thank me later.

 

[HOUSTON RICK]

Not a mechanic, but I keep cars for 250,000* miles, easiest potential fix could be fluid leak leaving insufficient transmission fluid? Refill periodically anticipate leak to accelerate over time.

 

[m1gunner]

Not a mechanic, but I keep cars for 250,000* miles, easiest potential fix could be fluid leak leaving insufficient transmission fluid? Refill periodically anticipate leak to accelerate over time.

Absolutely!

On ANY piece of equipment, you should check all fluids every time you use it, on a vehicle, at least once a week should be sufficient, unless it is a real "leaker".

One of my auto trannies tends to leak at the dipstick tube o-ring. The guy that overhauled it (24 years ago) didn't really know what he was doing. I know this as a fact, as I overhauled it myself. If it jumps out of gear, it is low on fluid. Add a quart and it is good for 4 months, longer if driven daily. But I never drive a mile if it is low on fluid, and always have a spare quart with me. Like I said, 24 years and still going, it did get a full B&M heavy duty overhaul kit and valve body upgrade when it was out.

 

[yaktamer]

Okay, I checked the fluid and it looks/smells fine. Odd thing is that the fluid level is high. Last time I checked it was fine. Could some internal problem cause the high reading, i.e., something's clogged so the fluid isn't going everywhere it's supposed to? And thanks to PatriotX for the PM on this. Either way looks like I'll be spending a couple of the vacation days I was planning to take this week at the shop or car shopping (ugh).

 

[m1gunner]

The fluid doesn't have a milky appearance, does it?

 

[johngalt]

Seems like auto transmission issues are never cheap. Several years back my Tahoe started shifting very hard. The mechanic said it was slipping and went into a 'high pressure' mode, which caused the hard shifting.

Cracking it open to do anything means big $$$, so he suggested seeing if a flush fixed it. Otherwise, since doing any service at all is expensive, replace or rebuild it.

The flush worked for a couple years, then the problem came back. This time he said it was definitely done, time for a new one.

 

[yaktamer]

The fluid doesn't have a milky appearance, does it?

Nope. No bubbles, frothing or anything else to suggest a problem. Maybe a fluid and filter change will buy me another year or two. I'm going to take it in Thursday to have it looked at, so we'll see (crosses fingers). I just drove it about 25 miles with no issues at all, but it was all level ground, unlike yesterday when the problem arose on mountain grades.

 

[HalfStack]

Okay, I checked the fluid and it looks/smells fine. Odd thing is that the fluid level is high. Last time I checked it was fine. Could some internal problem cause the high reading, i.e., something's clogged so the fluid isn't going everywhere it's supposed to? And thanks to PatriotX for the PM on this. Either way looks like I'll be spending a couple of the vacation days I was planning to take this week at the shop or car shopping (ugh).

See what it says on the dipstick to check the level and do exactly that. You can get different readings from other conditions.

 

[unclebob]

I don't know if it will work for you, but I had a Plymouth Voyager that had a symptom called transmission shudder and my mechanic suggested GM limited slip rear axle lube rather than trans overhaul.
Surprisingly it worked for another 5 years before I gave it last rites...

 

[LVSteve]

The fluid doesn't have a milky appearance, does it?

I know where you are going with that, a failure of a transmission cooler buried within the water radiator. BTDT with a Firebird some years ago and had oil in the radiator catch tank. The Nissan Xterra may have a weakness in that area, too.

When was the transmission fluid last changed? 9 year old fluid would not be good.

 

[m1gunner]

I know where you are going with that, a failure of a transmission cooler buried within the water radiator. BTDT with a Firebird some years ago and had oil in the radiator catch tank. The Nissan Xterra may have a weakness in that area, too.

When was the transmission fluid last changed? 9 year old fluid would not be good.

I got a dose of it as well. I bought a truck that had been wrecked in the front end before I bought it, ruptured the cooler in the rad. Truck was repaired, but transmission had some water that stayed and circulated.Fluid was clean when I bought it. I drove it for a while before it gave trouble.

The tranny didn't quit, just slipped in the mountains pulling a trailer, and overheated, spewing fluid out the breather and dipstick tube.

Let it cool, added fluid, and drove it home with the trailer. Lightly loaded, you would never know. Pulled the pan and found most of my clutch linings laying in the bottom. I suspect it was quite milky before the seller changed the fluid.

Went through it completely, and got a reman torque converter, and never had any trouble again.