Hey all. New here. I have 182k miles on my 99 Tahoe LT 5.7. The last time I went to have it inspected (April) the guy told me I should have my transmission flushed due to discoloration and a possible burnt smell and look. Here is my freak out. I have heard NIGHTMARES about having this done only to then have the vehicle towed to a transmission shop for rebuild/replace/repair. I am second owner on the vehicle and honestly I know I have never had the transmission fluid changed nor flushed (please dont start throwing shoes at me).

To make my worrying even worse, it has just recently started to tremble when I mash the gas at high speed to make a passing manouver. I saw an older post about checking the mounts but mine are all in great shape.

What do you guys think? Take it to a tranny shop and bend over OR take the plunge and get the flush done and roll the dice? I am going to Vegas in a few weeks....

Thanks!

Patrick

 

i would start with the flush(cheaper for now) unless they try and tell you it's starting to take a turn on ya...is it the 4l60e?

 

Welcome to the forum.

 

It is OK to flush a trans with dark fluid. However when it smells burnt the it should NOT be touched unless you are prepared to buy a new trans. Are you sure that the tremble when mashing the gas is the trans and not a misfire. Most trans problems are not really like that but I find that most times I get a description like that it is a misfire.

 

Thanks for the welcome Shark! And thanks to the rest who have responded so quickly. I am going to get a second opinion on the "burnt" question and go from there. Something I noticed is a slight backfire in the header. This happens only when I am rolling along at say 10 miles an hour down a merge ramp onto the highway and mash the gas to get up to highway speed. Could it be related???

 

That is not related to the trans. But probally is related to the problem you are havibg

 

O2 sensors may need to be replaced? Are you throwing any codes or getting a CEL or SES light? When is the last time you did a tune up or major service?

Without knowing the previous service history on the truck, 182k+ is good life for a 4l60e.

 

bai78, that is a great looking Tahoe man. Thanks for trying to help me out on this. The O2 sensors, I am positive need to be replaced. My check engine light has come on in the past and I went to a local auto store and had them check and clear it. It was during the check that I discovered the O2's need replacing. Gotta save some money for them though. Last I checked they were around $100 each and if memory serves me correctly there are four?

On the tranny, I checked the fluid myself and it is red, to clear red, doesnt look "burnt". now i checked it when it was cool/warm and not at operating temp. Should I check it at operating temp? I also compared the smell on the dipstick to the smell from a brand new bottle of Trans fluid. Didnt seem much difference to me.

I put a tune up on it at 100k miles but probably need to do another one.

This has really been a great truck. I have owned it since 60k miles and the only thing I have replaced on it is a battery, serp belt, and an alternator. I wouldnt trade it for the world.

 

I think a tune up would help. Mine '98 has 195xxx miles and I think the tranny is starting to shudder. It used to have a "buck" in it going down the road at 70, tune up cleared that up. Next is a trans. flush and then hope for the best. If the tranny smokes, I'll probably get used one and stuff in 'er.