Vibration in 5th gear only....any ideas what it may be? (9 Viewers)

[deneric]

Hi All,

I jumped over from the FJ40 site to ask a question about my 93 truck. It's a V-6 5 speed with 32" tires and 4" lift. It just turned 200k a few months ago.

The problem is that for a while now when I shift into 5th gear a low growling/vibration type sound comes from what sounds like the rear diff. When I push the clutch pedal in the noise stops. It is only in 5th gear, no other. I put a centerforce dual friction clutch in many years ago (probably around 120k) but other than that no work has been done in the drivetrain that I know of (I bought it with 76k on it). There is no play in the rear driveline or pinion. My first thought was the rear diff, but wouldn't the sound be audible most all of the time? Perhaps some bearing in the tranny for 5th gear? Anyone that may have had a similar experience please help. This is my daily driver and I would prefer to fix the problem before it gets $$$$$$. Hopefully someone can give me a direction to head in. Thanks in advance!

Eric

 

[inkpot]

Howdy! the 5th gear setup in the mini truck trannys is a known weak link. From what I have heard/read the problem is lack of proper lubrication. It the gearbox is low on lube all, it will reduce the ability to lube up 5th gear. Only a rumor, but my 85 mini does whine in 5th, but not any other gear. Maybe due to the same reason. John

 

[2ndGenToyotaFan]

I think inkpot's on the right track, the 5th gear bearing is smaller than the others (to fit inside the smaller gear...) and tends to be the first to go.... Check the fluid, maybe change it out if it's due, but it sounds like it's time to get in their and change a bearing.

If the noise only shows in 5th at the same speeds (IE 50 mph in 4th gear and 50 mph in 5th gear) Then I'd rule out the rear drive shaft and pinion... It may sound like it's coming from the rear, but it may just be fooling you....

 

[Jukelemon]

I agree with the above.

That is exactly the same issue issue I had with my tranny and it was found that 5th gear was worn. R and P's really last for quite a while if properly lubed-for that matter, under normal conditions, I have seen them last way longer than than the engine.

That vibration that goes away when you press the clutch is a good indication of tranny issues.

I found my replacement on ebay. Really lucky and it was a good option at the time.

 

[Hilux]

If its got extended cab check the mid shaft bearing.

 

[deneric]

Thanks for the input everyone. I will check the fluid level. I check it at every oil change, but you never know. I will also check the mid bearing as well. Hopefully I can hold off until the summer so I don't get rained on in the driveway. I need to change out a front axle anyway. Cheers!

 

[deneric]

Tranny mechanic says tranny is fine. Looking into u-joints. Toyota are $78 each or I can get all 3 for rear driveline for about $90 at NAPA. I am a fairly competent mechanic, but don't mess with u-joints much. How difficult of a job is it to replace them? Any special tools? I have a vice and a BFH...is that enough?

 

[deneric]

Just read in another thread that it isn't that bad of a job. I agree that toyota u-joints and bearings are worth the money, but I only drive my truck about 2000 miles a year and I only wheel in the FJ40. I know the u-joints in the truck are original, but Toyota quoted me $79 for each joint. My wife is probably getting laid off next month, so every $ is going to be needed to pay for the basics. Since I don't drive it a ton, I am hoping that the NAPA bearings will suffice. If anyone has experience on non toyota joints blowing up all the time please let me know.

Eric

 

[Jukelemon]

Hi.

I have first hand experience with non OEM U Joints failing. 2 times actually in 12k miles. That is terrible in my opinion.

I would check with Cdan to see what his price will be. As well, check to see if your Toyota dealer offers a 15% TLCA discount.

Nappa's high end joints are like 20.00 I think.