Is diff drop necessary?

Does the womping sound like it’s a sound the tire would make? Kinda sounds like that’s a word I would use for a tire sound…

Is there anything stuck in the treads, like a tar snake?

 

What dealership? We’re moving to Tucson in a couple of weeks and it’d be good to know who to avoid. We just came back from a road trip from Tucson / Vail and took my Tundra to Desert Toyota to repair the driver side window that had came off its track. The service manager made it a point to squeeze us in when I explained we were from Idaho and headed back that day (Monday morning) and the window issue happened the day before. It was a $175 repair that I was happy to pay and grateful for them getting us in.

 

My opinion is that both dealerships stink. Of the two, the only one I consider for service is Desert Toyota. Kyle is my guy there. Precision Toyota is horrible. I wouldn't buy a vehicle from either. I purchased my '22 ORP from Auto Nation in Tempe.

 

@McSpazatron yeah it definitely sounds like it’s from a tire. When I slow down almost to a complete stop I can hear it go “whoomp whomp whoomp” lol. It’s been inspected now by the dealership and the guys who installed the tires and they can’t find anything abnormal. I can hear the sound, and I’ve never heard it before this week. But when they’re driving it or riding along they aren’t picking up on it. I’ll probably end up taking it to the 4x4 shop sometime this week.. Im being told it’s normal, but it’s weird because I’ve never heard it before and I’ve had it since April.

 

@Jackstraw it’s the auto mall dealership. If you need anything done, I would go to Trail Boss on Ina rd. Those guys were awesome

 

Not sure if you mentioned mileage on the tires? Maybe they’re just loud tires, or one of them is but not the others.

If they’re all loud, then maybe it’s just how those tires are. Since most tires get louder with miles (off-roadable tires even moreso), maybe that’s just what those toyos sound like as they age.

If you rotate them, and the whomping moves with a tire, then maybe it’s a bad tire.

Edit, make sure to inspect them all the way around for tar snakes or anything else that may have stuck to them…including the spot of the tire you parked on, because inevitably, that’s where it will be lol

 

@McSpazatron such helpful info. Thank you! I think I had around 2500 miles when I got them, now I’m at 10.8k miles. Nothing on them, and they all look like they’re in good shape. There’s no other odd things happening either - no vibrating, grinding, clanking, etc. Just the weird hum/whomp sound.

 

It would be great if you could try a different set of tires...

 

@glwood54 I still have the stock tires, it would suck to have to take everything off though lol. If it gets worse or gets louder, I’ll probably have to try something else.

 

Just came to post an update since I said I would.

Took the 4Runner in to an off road shop yesterday, they did agree that the diff drop would be a good idea. Couldn’t find the source of the weird buzzing noise. Today when I drove it, I got up to 60mph and the steering wheel started SLIGHTLY rocking from side to side (insert face palm here). It is also pulling to the right at 60mph. Going back to the tire shop again on Monday. I only have 11k miles on this thing, can’t believe I’m having these issues At this point, if the tire shop can’t find the issue then I’m going to have them put the stock tires back on and see if that takes care of any of these things I’m experiencing. I’ve read it could be an off balance wheel or need an alignment (just had one done in May when they put the tires on). I think it’s a tire issue at this point… the buzzing I’m hearing at 33mph and now the steering wheel rocking from side to side, aaaaand the “womp” sound on the tires. I had them put on at 2500 miles, so it’s weird they’re just now causing issues…. Anyway, there’s the update.. no answers and more new problems ((((

 

@tessakoz
Not to thread jack but did you install both the front and rear rough country lift or just the front? I have an extra set laying around and am considering putting it on my wife’s 22 off road but I only have the front just wanted to see what you had put on

 

By reading all of this and based on my experience with my 4R, I think it is the tires you chose (Toyo R/T). Having said that, the lift kit you installed is ok, but it could create a perfect storm of potential issues with the symptoms you described. Remember, you have modified the symmetry on the front as well as the leveling. The entire system is not the same as stock anymore. The 4R is very sensitive once we start moving things up or down and that's why at 60mph you find yourself with new issues. I also started with the leveling kit or lift kit as the one you showed in the picture, then I moved to a Wescott "Pre-collar" lift which is from the bottom up and not from the top, and yes there is a difference. Start troubleshooting from a process of elimination and go with small changes and see which one corrects the issue as you understand the vehicle. I know it is very frustrating spending money and time in understanding all of these new components, but this is part of the learning process when making changes to your 4R. Don't get mad at the 4R, it is a very capable vehicle and it looks great, so hang with it and keep trying until you find the optimal spot.

One of the things I have noticed with all of these larger tires is that over time they just need a lot re-balancing. I have even forced myself to get into the discount tire shop to learn how they do the balancing and while observing the process, you can see the tires in the machine doing an oval type rotation which tells you right there that these larger tires have imperfections and that's where the balancing comes in. In my opinion, it is more of an art in tuning and tweaking all of these parts and components than an exact science. Some of the shops my get frustrated with you, but don't worry, you are paying anyway. Find a place that would take their time and would give you and teach you the reasons as to why this is happening.
Two of my favorite quotes that I have heard from all of these "expert mechanics" are: 1. You want your 4R to ride like a cadillac. 2. You are on the wrong vehicle. And I say, well, I want my vehicle to look a certain way and to ride a certain way, so. Hang in there and send more pics and updates.

 

Of course they did. They couldn't make money by telling you not to bother.

Have you confirmed that it isn't the needle bearing? Sorry if this was covered already.

There's definitely a chance the tires are the problem. Those are fairly aggressive tires. True mud tires tend to have a woomp, woomp, woomp sound at some speeds.

Were they rotated after 5K miles?

 

@ChessGuy thank you for all the info! I don’t think it’s the 4r itself at this point, I’m convinced it is the tires. We don’t have the spacers on the back, just the front. I don’t mind noise, my husband has a huge lifted Chevy with an overland tent and it’s a beast - loud as hell haha. I just know that what I’m hearing isn’t normal so it’s more of figuring out what my 4r isn’t liking lol so I can fix it. Also, the wheel slightly rocking back and forth at the highway speeds freaks me out because I know it’s not a normal feeling. It seems to just shimmy from side to side, and the car pulls heavy to the right. It’s only at like 58-60mph. I’m thinking that tomorrow if the tire guys can’t find anything wrong, I’ll have them put the stock tires back on and I’ll drive it for a day and see if everything stops. If it does, then I’ll know it’s the tires and I’ll probably have to find new ones. My husband has Toyo tires on his Chevy and we have taken that thing down every rough road, driven thousands of miles, and they’ve been great. Maybe just not a good fit for the 4r though

 

@Thatbassguy it still makes all the noises in 4wd, and Toyota did check and say it wasn’t the needle bearing. That was the first thing I asked them about when I dropped it off. We did rotate the tires at 5k miles. It’s making that womp sound when I’m coming to an almost complete stop, or while turning left/right. Only at very slow speeds. It almost sounds like a rubbing noise, but there’s nothing for them to rub against.

 

@enjm1021 we only have them on the front

 

It does sound like it could be the tires. Maybe a less aggressive tire would help.

You mention having them put the stock tires back on. Do you have the stock tires on wheels? Or, did you have your new tires put on the stock wheels?

 

@Thatbassguy I still have the stock tires and rims in our garage. Right now the current setup is 33in Toyo tires (pretty sure they’re the all terrain ones), 17in kmc rims, and the 2in rough country leveling kit.

 

I guess if you have time one day, you could always swap the stock tires and wheels back on and take it for a ride just to isolate the issue. Kind of a hassle, But at least then you could confirm whether or not it is the tires.

 

@Thatbassguy yeah that’s the plan. The tire guys are gonna check tomorrow to see if I lost the weight in a tire or anything like that - balance issues, etc. With it pulling right I think there’s something with the alignment…so that’s annoying lol. I’ll let them do their thing and see what they say. After I pick it up and drive it, if it’s still doing it, I’ll head back and swap the tires. I don’t really see another option, I don’t want to drive it like this and have it create an even worse problem ya know.

 

This is good stuff folks. Good for you @tessakoz for taking the time and energy to investigate thoroughly. It sounds like you have been around the block a few times!

 

@Ironguy thanks haha. I’ve had bad experiences with mechanics when I was younger and had a lot of car problems with my Honda. This 4r is my first brand new car, she’s my baby. I just like knowing what I’m talking about when I take it in, so they don’t automatically see a chick and think I don’t know anything lol. I appreciate everyone’s input too! It helps a ton!!

 

Mine was the same. With the ~2.5" lift I got, the angle was very similar, just down instead of up.

 

I’m heading a weird buzzing noise on the left driver side at 33mph, I posted another thread about it. The off road shop I took it to looked at everything and said it was fine, and said I didn’t need the drop. They couldn’t get it to make the sound, so I went in and took them out and they finally heard it. After that, they were looking at everything again and they said there was a weird sticky substance on the boots, they said they think it’s the boot rubbing against itself and creating this sticky stuff (weird?) So after seeing that, then they said the drop would help. They did tell me it wasn’t necessary and if I drove it without it, it would be fine - but that the drop would help with things not wearing as fast. So it was more like, “you can do it but you don’t have to” type of recommendation. Now I’m more concerned with tackling this damn wheel/tire issue than the diff drop lol. I think all the noises and things I’m hearing are attributed to the tires. I went to the pumpkin patch tonight and it’s a big lot made of dirt and rocks, when I turned in and only going 5mph the whole damn steering wheel was rocking back and forth.

 

Hearing** not heading lol

 

This thread may be dead. Back on 9/30/22 Tessakoz posted pics of the angles on her SR5. Thinking of a 2.5 inch spacer front just to get rid of the rake…..questioning if diff drop is really an option. It’s cheap I know but…..her pic showed this.



I took a pic of our 2023 Off Road Premium still still stock. It looks like this:



Comparing the 2…our stock looks like is has a negative tilt? Am I crazy?

so if so, a 2.5 spacer with settling likely down to around 2-2.25 that may brings ours to level????

 

I did 3" suspension lift and true 33's
I had 4WheelParts install diff drop kit, $42 CAD + labor
Here is my angle if it helps

 

Mine was a bit “negative” cv angle before my lift. I would guess a 1.5 to 2in lift would give you a level cv axle. Don’t count on “settling”. Some supsension lift kits run high.

 

Very similar positive tilt angle
2" RC lift no diff drop
Vs
3" lift and 33's and diff drop kit

 

Thx! Very Helpful.

The more info the better ( we are Coming from the jeep fixed axle to the 4R’s IFS and it is a little different).

May just end up going with an OME or Bilstein kit and call it a day.