2000 Yukon Maintenance Question

[NotJLB]

thanks

coolant change only

FWIW, the local mechanic I went to said to just change the tranny fluid and filter. I explained what y'all have been saying, and he said that it may crap out if I do that.

 

[NotJLB]

That kind of sucks. Especially if you bought your vehicle used and the PO has no idea what work was done to it because they never cared enough.
I bought my Tahoe with about 130k on the clock and bought it from a dealership so they had no service records. Guess I lucked out. I just changed my fluid with about 160k on it and so far everything has worked out fine. Fluid was a good red color so guess it may have been changed at 100k. Only put about 10k on it since the change but it's been good so far for me.

Guess it's a YMMV kind of thing. Whichever way you go good luck.

Good point.

New question.

Now that I'm paying attention, the tranny service interval is 45,000.

If you buy a used vehicle, assume the tranny has never been serviced, and you are going to do that right away, at what mileage is it too high to start servicing the tranny?

 

[rv8pilot]

Ok, here's my two cents: I have a 2001 Yukon XL acquired two years ago with 231,000 miles and very little maintenance other than oil changes and replacing what failed. None of the fluids other than the oil had been changed since new. Nor had the trans filter been changed. After taking care of the obvious problems, water pump, alternator, etc., I changed all the fluids including the trans. I flushed the transmission using about three gallons of ATF, drove it for a day or two and flushed it again this time using synthetic fluid. I have not had a single transmission issue. Here in Florida and in other hot climates the brake fluid does not hold up well. I flushed it out with fresh fluid and I do this every two years regardless of the mileage. I can understand that introducing fresh fluid in a dirty transmission could cause the release of abrasive particles but if there was that much friction material in the trans it was probably past due for an overhaul. I was surprised by the clean condition of the pan and valve body in my trans after that much mileage. I previously had a 1991 Aerostar van with the A4LD trans and at 100,000 miles there was a good quarter inch of crud on every surface. I think the difference is the use of synthetic fluid originally by GM. Your mileage may vary.

 

[NotJLB]

Good point.

New question.

Now that I'm paying attention, the tranny service interval is 45,000.

If you buy a used vehicle, assume the tranny has never been serviced, and you are going to do that right away, at what mileage is it too high to start servicing the tranny?

I still want to know that, but, seriously, how many people service their transmission every 45,000 miles?

 

[mizzouguy]

I still want to know that, but, seriously, how many people service their transmission every 45,000 miles?

i do every 50k. Cheaper than a new tranny.

 

[NotJLB]

i do every 50k. Cheaper than a new tranny.

I still want to know that, but, seriously, how many people service their transmission every 45,000 miles?

one

Table Rock Lake here

 

[06Escalade]

My opinion on this post..

Don't think I would ever "flush" anything. Flush means use pressure other than the transmissions own pump during a fluid change. I can see that causing a host of problems, new or old transmission. I think most lube places today use an "exchange" machine, which is mainly a containment vessel for fluid in and out. An exchange primarily uses the transmission's pump. Or perhaps the word flush has been misused all along.

A pan drop for a filter and fluid change only removes approx 33% of the total fluid in the transmission. Which means the new filter is fouled with junk from old fluid soon after its replaced. I do a full exchange prior to the filter swap via the top radiator return hose. This minimizes the new filter exposure to contaminants from old fluid. So when I do get around to dropping the pan the fluid is relatively clean.

Rumor has it a flush/exchange/change on an old neglected transmission can ruin it, cause problems. Partially true, but that does not mean something in the transmission is guaranteed to go wrong. What is guaranteed is doing nothing will inevitably result in transmission failure. Because transmission fluid is the hydraulics, lube and coolant. If severely neglected, the fluid no longer cools the transmission, it continually overheats, clutch plates burn up and wear out. In some cases the crud and debris from burnt clutches, seals, gears, etc. serves as friction material which allows the worn out clutch plates to still grab enough to shift. These are the 10% of transmissions that perpetuate the rumor. Remove the debris with nice clean fluid, the transmission starts to slip. No, the fluid didn't cause the transmission to blow. It exposed the inevitable failure due to years of neglect and being a cheapskate. So, its hit or miss. No one can say for sure that swapping out the fluid on an old, neglected transmission won't cause a problem. But its still better than doing nothing.

 

[NotJLB]

The indecision thus becomes more indecisive.

 

[PG01]

Are you keeping this truck forever? Honestly at over 225k something major may happen, not because GM sucks, just because....thats life. Hopefully not but if it blows, it blows get it rebuilt and drive it until the motor goes, or tcase or diffs.... i have always believed in preventative maintenance but shit happens, maintaned or not. You let it slide for this long and no use harping over it now. Drive it till it goes but hope for the best... not saying you're at fault and i know you have done other things but this is what you got now so and you're asking for advice. Im not being a dick if it sounds that just saying drive the ****** till you cant drive it no more at this point..... or sell it now and get something else. Hope this helps your decision.

 

[NotJLB]

Not harping . . . looking for advice.

Generally agree.

I now have options as to what advice to follow. Service the transmission and don't service the transmission.

I have two possible plans.

1. Purchase another vehicle, and be more diligent, thus my question, and the only relevant one at this point . . . What is the highest mileage used vehicle I should buy, assuming the transmission has never been serviced?

45,000? 60,000? 75,000? 90,000? More?

2. Keep driving what we have, towing our new little camping trailer 1200 miles to Florida, knowing it will crap out some place, some time, and hoping the natives will be friendly. Then buy another rig in Florida. The crapshoot . . . can we get one more trip out of it?

The third option, which seems a tad sketchy at this point, is to service (not flush) the transmission before 2.

#4, I guess . . . don't ever go anywhere again.