Initial symptoms on tranny failure?

So this obviously is hard to diagnose over a forum but here goes. I bought my 02 SR5 4wd V8 A/T a year ago. Prior owner (original owner) kept excellent records of all maintenance and service records and was punctual on fluid changes, etc. I changed the tranny oil about 5-6 or so months ago and it was pretty clean, red, etc. He mentioned he used to have a 25' 5th wheel he towed a few times camping but wasn't able to tell me the weight so either hiding that info or just didn't know if he was maxing it out towing. I added 33x11.5" tires and a 2.5" lift a year ago and had no problems up till about a few months ago. Again, I changed the fluid about 6 months ago. 245,000 miles on the rig. Anyway, about few months ago started noticing that on level road, from 45mph to cruising to 75mph or so, highway, I get this intermitted light jolt as if the tranny is shifting but I do NOT see actual rpm shift. It's as if a clutch is engaging and disengaging. Very slight jolt. I don't believe it's a fuel feeding issue as it feels more so like coming from the driveline. No check lights, no feel of slippage in forward or reverse. Acceleration is fine. It does this same thing in OD also. I've not towed anything with it since I bought it. Thoughts? Thanks for the advice.

RB

 

Have you greased all the U-joints and slip yoke? I was getting a low speed jolt that went away after greasing the slip joke. Worth a try.


Edit- worth***

 

Wort

 

I've actually done the U-joints around same time but what is the slip yoke? I'll give it a try.

 

Actually, just looked up a picture. lol! I think I have if when greasing the tip on the U-joint spreads grease out the side of the bearing, right? Would that not also grease both assemblies? But how would these be going dry start causing a jolting sensation intermitted every few minutes or so in steady cruise?

 

The slip yoke is a separate zerk fitting from the U-joints. It may not be the cause of your issue but it would at least be something you could try to rule it out.


Read this old post.

https://www.tundras.com/threads/jolt-when-stopping-at-a-light.60699/#post-1590947

 

Ok thanks pal. I'll have to check it out.

 

I've never driven a 1st gen...some cars will noticably jolt when the A/C clutch engages. Usually that is a idle or very low speed though.

 

Just adding two points on it.

One, I never saw grease come out when I greased the slip yoke, and I pumped a couple dozen times. I did see it move in/out a bit. So it's not like that's a necessity, but I was having clunks with stopping/starting/etc. and greasing the driveline fixed. It was driving me nuts.

Two, check this diagram, it'll show you the zerks. (B) in the diagram mas my issue, but really, you should be hitting them all every oil change or 5k miles per maintenance schedule, if I remember right.

https://www.tundras.com/threads/jolt-when-stopping-at-a-light.60699/#post-1590863

 

I've had that issue in another vehicle at "off the line" but in this case, start and stopping isn't the issue, it seems to happen cruising on level road. As I approach a hill or going downhill, then it shifts fine up or down. Just seems at highest gear, there is this annoying slight and subtle light jolt like feeling intermitted, like I mentioned in original post. Will have to start diagnosing.

 

I've greased them about 6 months ago when I performed the tranny oil change. Nice diagram!

 

Are you 100% positive your fluid is at the proper level? Sorry if I missed you confirming that already. I'm pretty sure your '02 still had a dipstick. You're lucky if so, my '06 is sealed.

 

Have u checked your rear end. I have seen some recommendations on here when using bigger tires might need to upgrade to a different ratio.

 

Don’t have a 1st Gen, but the transmission went out on my 2018 Silverado I drive for work. It started downshifting really hard when coming to a stop, and then it started slipping on any incline.

 

Found the problem!

Seriously though, former lifetime GM guy here. Ever since GM moved away from the 700R4, almost every electronic transmission they've made in the same class, starting with the 4l60e, has been pretty much 100k mile trash at best.

 

The entire truck is a piece of shit.

 

GM pickups really started to go downhill starting with the GMT400 platform. The engines got more advanced, but everything else went down the toilet.

 

It's been a while since I checked it but I've checked underneath and no leaks, but I will check. Also yes, the plan is to go with a different ratio. I'll be going with 4:56 gearing from 2002 Toyota Tundra Yukon Ring & Pinion Package | RealTruck. Actually, good time to ask if anyone has experience with this set up. This video has good info on how to calculate the ratio so I ended up with the next option of 4:56 gearing. How to Choose Your Axle Gear Ratio - YouTube. Anyway, not sure if the gearing would fix this issue but when I get back from my trip I'll check the oil. Not driving it right now anyway.

 

My first gen I can tell on the freeway at 70mph when the clutch kicks on and off. At first I thought it was a misfire. Glad it wasn’t, I’ve chased misfires before, not fun.

 

A misfire or a tranny shudder? This could be the OPs experience.

 

I thought about that too thinking maybe there is a mis-fire but since it feels more so in my "butt and back" per-say, it feels more so coming from the drive train. Interesting though Diablo above just mentioned the A/C clutch. I'm away in training and my wife just mentioned she heard some noise, and a buddy mentioned it was the A/C clutch. Last week when I drove it, I didn't notice any issues with the A/C clutch noise but perhaps as it kicks on/off it's causing some sort of shutter. I find that hard to believe that little clutch could cause that with experience on my 99 exploder's clutch (new) and even when I changed it on an older compressor some years ago, as it kicks on and off, there is no shutter to speak of through the drive train. Different vehicle of course but worth investigating. To add though, I feel this shutter even with the A/C off so the clutch should be disengaged until activated.

 

That's weird. I've got 4l60e with 230k on the clock and haven't ever had a problem. It hauls the family of seven everywhere, up and over Cascade passes, sometimes with a 23' camper behind it. All I've ever done to it is install a bigger trans cooler. I know the 8sp autos had real problems. I've always heard pretty good things about the 6sp, though.

 

If you told me it was a 4l80e, I'd believe it. The 4l60e was created as a 'universal' (multi-vehicle/multi-purpose) transmission and it's really unusual for the 4l60e to last past 150k miles without needing a rebuild, unless you start regular maintenance early and keep up with it. Even still, you're not immune to, like, sudden loss of 3rd gear because seals have shrunk with age/miles. Are you sure you have the 60e and not the 80e?

There are a number of "driveway fixes" possible to make a 4l60e last a good 200k miles. Things you can replace, points you can drill for better fluid flow, upgraded solenoids, etc. to get around the factory flaws. There are plenty of companies out there who'll take a 4l60e and make it capable of handling assloads more power and miles. This is one of them: https://www.motortrend.com/how-to/how-to-build-a-4l60e-transmission-that-can-handle-1000-hp/

Note in that article he mentions "OEM flaws". It's no secret: The 4l60e has known-flaws from the factory. GM didn't fix them (soon enough) because they tend to last the "life of the vehicle", i.e. avg of 120k miles. I don't know if any of the issues were ever fixed after the 2000s, most of what I've dealt with in my lifetime was pre-'05, and I personally aimed for the 4l80e or something fun and manual like a T56. If you have a 4l60e and it's still going with 230k miles on the clock, knock on wood....

 

Keep in mind, if you have the climate control on defrost or defrost mix, the AC is on automatically, wether or not the AC button is pressed.

Unless you have disabled this feature, which I have.

 

This is a really good point. My truck typically staggers a little bit when the A/C kicks in on the interstate, almost feels like it loses a couple hundred RPM. Not a thud. But the earlier models may be different, and yours is a great point.

 

Sounds like torque converter shudder to me. At 250k miles you’re on borrowed time.

 

Unlikely...250 aint even that many miles.

 

You can always drop the pan and check the magnets and filter for debris. When my transmission started going out on my 2000 tundra @ 195K miles it developed weird vibration and a rough shift 3rd to 4th. When I took it apart the Torrington bearing for the front overdrive planetary was almost completely gone along with some chipped teeth on the sun gear.

 

Your lucky! You probably have an older 4l60? Most chevy transmission are trash because they tune them to shift extremely smooth which wears the clutchs out. Also have torque on demand bullshit so it always feels like your driving a slushie

 

Saw this and laughed. My 2017 silverado work truck is at the shop as we speak getting transmission #3 put in at 109k miles. First one blew at 74k, this one barely made it 35k. But to speak to OPs experience and indicates.. was fine until it started slipping out of gear, slamming into gear randomly and shaking the whole truck, winding itself silly before shifting on flat ground, etc. We have telemetry/GPS trackers in our trucks so I drive like a grandma and we arent allowed to tow anything so it shouldnt be shitting through trannys like that. But then again the whole truck has been a giant steaming pile of dog shit so who tf knows.
My husbands 2003 Tundra has 300k on it and has never had any issues and only routine maintenance.