Drivetrain Problems after Timing Belt Replacement

[Hokie-Pokie VT]

So my 3rd gen just rolled over 235k miles, I'm also not an idiot and know that the car is old, and Im a somewhat decent engine mechanic, but I don't have a lot of knowledge in drivetrain components.

I had the timing belt replaced about 2 weeks ago at an independent shop I trust. Engine hums along, nothing wrong with it. Before this job was done, my 4R drove just fine for the most part for a vehicle with over 200k. Smooth as butter on my highway commute to work.

On the drive back from the shop, i noticed a considerable shake at 40+ in the drivetrain, meaning i could feel it in the seat and pedals like it was coming from beneath/behind me, not so much from the front/through the steering wheel. I take it back to the shop and they determined that one of the U-joints had gone bad. Another $120, no big deal.

So now I have it back again from the shop, and I have more shaking, this one is occurring in 2 different ways. One is very obvious, at 65+ at cruising throttle/speed, I get this rhythmic rumble. Meaning it comes and goes in a U-shape, it builds to a max then backs off, and repeats. Again it doesnt feel like its coming from the front.

The other weird feeling is when "creeping" forward. I feel like the truck doesnt just roll forward or "creep" when I let off the brake pedal at a standstill. And when I am slowly rolling forward (no input on accel or brake pedal), it feels like the vehicle rolls normally, then slows down, and repeats. almost like its getting caught on something in the drivetrain. Notice this is a similar rhythmic pattern like the one i mentioned above.

Now the shop said something like since the timing belt was done, it tightened up the whole engine and that it may be the torque converter. Unbeknownst to them, about a year ago i sprung a leak in my external trans cooler and ran the transmission low on fluid, so while I know that, they don't, but still I don't know if that makes sense to me. (Lack of drivetrain and transmission knowledge).

So any insight would be appreciated. I don't know what doing the timing belt would have done to cause these seemingly not-related-to-the-timing-belt issues to arise. The U-joint i just choked it up to coincidence, but the fact that I STILL have this ruble has me worried. I have to drive 30 mins round trip out into the sticks to get to this shop, so I'm really regretting having to take it out there to them again.

 

[99SC4Runner]

I don't think I'd take it back to that shop since it seems as they don't know how to correctly troubleshoot/diagnose issues.

Do you have some place out of the weather to jack the rig up off the ground and start checking out the drivetrain?

Are the driveshaft yokes timed correctly with each other on the driveshafts? Check wheel bearings for play and dragging conditions.

 

[octanejunkie]

Universal on the rear drive shaft doing bad is my guess

Edited to qualify

 

[Hokie-Pokie VT]

I don't think I'd take it back to that shop since it seems as they don't know how to correctly troubleshoot/diagnose issues.

Do you have some place out of the weather to jack the rig up off the ground and start checking out the drivetrain?

Are the driveshaft yokes timed correctly with each other on the driveshafts? Check wheel bearings for play and dragging conditions.

Yeah I can do that. Do I need to get all 4 wheels off the ground to check? I figure if you can twist any of the forward or rear facing driveshafts and they have play in them that is bad, but is there anything else to do to check out the drivetrain that you or anyone else can recommend?

 

[phattyduck]

Yeah I can do that. Do I need to get all 4 wheels off the ground to check? I figure if you can twist any of the forward or rear facing driveshafts and they have play in them that is bad, but is there anything else to do to check out the drivetrain that you or anyone else can recommend?

Front driveshaft won't be doing much in 2WD. It'll be the rear.

You just need the rear axle up and trans in neutral to check. Make sure to chock the front wheels since you won't have anything to stop it from rolling.

You will likely need to pull the rear bolts (at least) to check the joint operation. Maybe they rebuilt the double cardan with the wrong parts or something? (the double cardan can't easily be rebuilt - correct parts are very hard to find)

-Charlie

 

[gamefreakgc]

If you want to rule in or out the rear driveshaft completely you can remove the rear driveshaft entirely and drive around in 4WD, which is now front wheel drive. I did this once to try and diagnose some rythmic vibrations I had around 60 MPH but in my case it's not the driveshaft, it's something in the front end.

It comes out with 8 bolts; 4 on each end. You may need a rachteting box wrench to get the bolts off as they are sort of tricky to get to as there's a bolt and nut on both ends and requires you to hold both ends in place or sometimes the bolt and nut will just spin. Putting it into N, rotating the driveshaft it to an easy to access location and then shifting back to P helps it not rotate on its own when you are removing the nuts and bolst. It's easier to remove the rear differential end first and then do the transfer case if you choose to jack up the rear end. Mark the position of the transfer case and driveshaft with some white tape or whiteout and do the same with the rear differential and the driveshaft before removal. It's not completely necessary but since you aren't balancing it, just removing it, it helps to put it back in the same position. Then just pop it into 4WD and take it up to speed where you had the vibrations. If it is gone you've found the problem. If it isn't then your driveshaft is good. Might as well grease it with a grease gun on the zerks while you have it out and accessible as well.

 

[phattyduck]

Might as well grease it with a grease gun on the zerks while you have it out and accessible as well.

Using the Ford PTFE drive shaft grease after cleaning the splines helps keep the stop/start clunk at bay too. You do have to make sure to re-align it correctly when you put the shaft back together...

This is a good reminder that I need to grease my driveshafts at my next oil change...

-Charlie

 

[FD7683]

When I replaced the original timing belt on my truck at 220k the engine ran way smoother than I thought it would. Runs so smooth the rattle I used to have from the muffler at idle went away (still replaced it with a new one couple weeks after the TB overhaul).

 

[Bad Luck]

The other weird feeling is when "creeping" forward. I feel like the truck doesnt just roll forward or "creep" when I let off the brake pedal at a standstill. And when I am slowly rolling forward (no input on accel or brake pedal), it feels like the vehicle rolls normally, then slows down, and repeats. almost like its getting caught on something in the drivetrain. Notice this is a similar rhythmic pattern like the one i mentioned above.

Now the shop said something like since the timing belt was done, it tightened up the whole engine and that it may be the torque converter. Unbeknownst to them, about a year ago i sprung a leak in my external trans cooler and ran the transmission low on fluid, so while I know that, they don't, but still I don't know if that makes sense to me. (Lack of drivetrain and transmission knowledge).

So any insight would be appreciated. I don't know what doing the timing belt would have done to cause these seemingly not-related-to-the-timing-belt issues to arise. The U-joint i just choked it up to coincidence, but the fact that I STILL have this ruble has me worried. I have to drive 30 mins round trip out into the sticks to get to this shop, so I'm really regretting having to take it out there to them again.

First off, that whole section I put in bold is complete horse feces. They're just making stuff up now to try to get you off their back. I hope they don't actually believe any of that themselves, and if they do that's even worse.

Secondly, the creeping slowing/speeding up sounds to me like something to do with your rear brakes. It could be warped drums, a stuck/sticking bell crank, or even a bad axle seal causing the rear drums to get coated in gear oil. While you are driving (try this around 20 mph then around 50-60 mph) pull up on the parking brake handle while holding the release button. If the vehicle shakes or pulsates then you have a problem with your rear brakes.

Thirdly, gamefreakgc suggested it before I could, but removing the driveshaft and driving around in 4hi will eliminate the rear driveshaft being the issue.

 

[gamefreakgc]

Secondly, the creeping slowing/speeding up sounds to me like something to do with your rear brakes. It could be warped drums, a stuck/sticking bell crank, or even a bad axle seal causing the rear drums to get coated in gear oil. While you are driving (try this around 20 mph then around 50-60 mph) pull up on the parking brake handle while holding the release button. If the vehicle shakes or pulsates then you have a problem with your rear brakes.

I forgot that this happened to me under light braking when my axle seals failed a total of 3 times. It would grab, then release, and grab, and release with each tire rotation.

 

[3bears]

sorry, but in my brain, there is no way your symptoms are related to a timing belt change.

 

[Hokie-Pokie VT]

Alright sports fans,

So its the rear brakes on the passenger side or a wheel bearing. We have our first warm day here in VA and driving through my neighborhood there is a NOTICABLE squeal and rubbing sound when I am moving that pulses (like the pulsing sensation I was describing in my first post).

For funsies, I took it to my work where we have a porta-lift and got all 4 wheels off the ground. I took a series of short vids, liked to YouTube below.

4Runner Rear Brakes and Driveshaft - YouTube - Link to the playlist, 7 vids, all short, less than 1 min each.

What I failed to mention when I first posted (cause honestly I just always assume worst case scenario), is that when they did the T-belt I mentioned that my parking brake had new shoes installed a few months ago, but that the parking brake didn't seem to be quite as taught as I would like and if they could inspect and adjust them. So they did, and sure enough, the p-brake worked great when I got it back. So when I took it back to them and said to inspect and figure out the shimmy, I asked them to check over their work from the rear brakes and they said, if you don't smell them, its not the rear brakes. I didn't smell them, so i figured Ok.

Anyways, check out the vids and let me know if I'm missing anything, I'm going to call the shop and let them know Ill be taking the vehicle to another place in town and having them correct the work and that they will be billed for it. That's reasonable, right?

 

[Endlessblockades]

Good use of YT vids - sorry, I'm not a mechanic but will be watching to learn. Good luck, man.

 

[Bad Luck]

Alright sports fans,

So its the rear brakes on the passenger side or a wheel bearing. We have our first warm day here in VA and driving through my neighborhood there is a NOTICABLE squeal and rubbing sound when I am moving that pulses (like the pulsing sensation I was describing in my first post).

For funsies, I took it to my work where we have a porta-lift and got all 4 wheels off the ground. I took a series of short vids, liked to YouTube below.

4Runner Rear Brakes and Driveshaft - YouTube - Link to the playlist, 7 vids, all short, less than 1 min each.

What I failed to mention when I first posted (cause honestly I just always assume worst case scenario), is that when they did the T-belt I mentioned that my parking brake had new shoes installed a few months ago, but that the parking brake didn't seem to be quite as taught as I would like and if they could inspect and adjust them. So they did, and sure enough, the p-brake worked great when I got it back. So when I took it back to them and said to inspect and figure out the shimmy, I asked them to check over their work from the rear brakes and they said, if you don't smell them, its not the rear brakes. I didn't smell them, so i figured Ok.

Anyways, check out the vids and let me know if I'm missing anything, I'm going to call the shop and let them know Ill be taking the vehicle to another place in town and having them correct the work and that they will be billed for it. That's reasonable, right?

You need to talk with the shop that did the work before going somewhere else and expecting them to pay for it without taking them to court. You might have the best luck trying to get a refund for the brake work done.

More than likely they did not adjust the rear shoes correctly so the one side not gripping with the parking brake engaged is too loose and the other side that is dragging all the time is too tight.

You might also have a seized bell crank as well causing the parking brake to be stuck on at the right rear backing plate. To check for that follow the parking brake cable to the backing plate. The cable attaches to a metal arm which is the bell crank. On the bell crank there is a bolt threaded into it. With the parking brake off the tip of the bolt should be within 1/32 of an inch from the backing plate. If you have more gap then that then the bell crank is seized. If you don’t then most likely they over adjusted the brake pads. Here’s a link to what you should be looking for: https://www.toyota-4runner.org/2741095-post1.html figure 19 shows the bell crank and “C” is the 1/32” gap you are looking for. Also check to make sure the left bell crank moves when you engage/disengage the parking brake.

Either way you should find somewhere else to take your vehicle and tell everyone you know not to go there. Unacceptable work and a disgrace to my profession.

 

[Sparky 97Runner]

Now the shop said something like since the timing belt was done, it tightened up the whole engine and that it may be the torque converter.

LOL. This is a giant BS thing for them to say. Any chance that the shop took your rig 4wheeling while they had it and broke something?

 

[Hokie-Pokie VT]

LOL. This is a giant BS thing for them to say. Any chance that the shop took your rig 4wheeling while they had it and broke something?

I know that they had some sort of explanation as to why this could be the case, but it made so little sense I just blew it off I cant even really remember what they actually said. But I know for sure that the point he was trying to make about it not creeping forward correctly was cause it was the TC. Idk. Still makes no sense.

 

[Hokie-Pokie VT]

You need to talk with the shop that did the work before going somewhere else and expecting them to pay for it without taking them to court. You might have the best luck trying to get a refund for the brake work done.

More than likely they did not adjust the rear shoes correctly so the one side not gripping with the parking brake engaged is too loose and the other side that is dragging all the time is too tight.

You might also have a seized bell crank as well causing the parking brake to be stuck on at the right rear backing plate. To check for that follow the parking brake cable to the backing plate. The cable attaches to a metal arm which is the bell crank. On the bell crank there is a bolt threaded into it. With the parking brake off the tip of the bolt should be within 1/32 of an inch from the backing plate. If you have more gap then that then the bell crank is seized. If you don’t then most likely they over adjusted the brake pads. Here’s a link to what you should be looking for: https://www.toyota-4runner.org/2741095-post1.html figure 19 shows the bell crank and “C” is the 1/32” gap you are looking for. Also check to make sure the left bell crank moves when you engage/disengage the parking brake.

Either way you should find somewhere else to take your vehicle and tell everyone you know not to go there. Unacceptable work and a disgrace to my profession.

Assuming this involves removing the drum? Its hard for me to work on my car these days, I live in a townhome and have a small, not-level parking space. So i have to drive across town to where I work on the weekends. Really not trying to be driving this thing more than I have to after finding this condition. But I appreciate the thorough response. Depending on what the shop says, I may be doing this. Guess there's no time like the present to learn about all the intricoes of the rear brake mechanism.

 

[Bad Luck]

Assuming this involves removing the drum? Its hard for me to work on my car these days, I live in a townhome and have a small, not-level parking space. So i have to drive across town to where I work on the weekends. Really not trying to be driving this thing more than I have to after finding this condition. But I appreciate the thorough response. Depending on what the shop says, I may be doing this. Guess there's no time like the present to learn about all the intricoes of the rear brake mechanism.

It really depends on what is wrong with it. You can check the bell cranks with the vehicle on the ground. The bell cranks are on the backing plate for the drum brakes so it's visible if you slide under the back. If you click on the link I included it will show you what you're looking for.