Engine & Transmission mounts - should they be replaced at 330K miles (1 Viewer)

[South Texas 97]

Folks, question to the experts (although I am sure everyone will chime in)
As I work my way through my 97 with 330K miles on the clock, I do see some small cracks on the outside of the transmission mount rubber. What does the collective experience tell me about engine and transmission mounts - do they have an impact on how the vehicle feels, and what are the criteria to replace them?

 

[Bludozer]

Folks, question to the experts (although I am sure everyone will chime in)
As I work my way through my 97 with 330K miles on the clock, I do see some small cracks on the outside of the transmission mount rubber. What does the collective experience tell me about engine and transmission mounts - do they have an impact on how the vehicle feels, and what are the criteria to replace them?

At 330k, I wouldn't go in there and pull it all apart just for the mounts if you aren't having any issues with them. But if you are going through it fully, refreshing and pulling it apart anyway, I certainly wouldn't put it back together with the old 330k mounts.

 

[Irish Reiver]

Not sure that mileage is more of a factor than age. I replaced mine last year. My truck had about half of what yours had but was 26 years old. The old mounts were hard but not cracked or split. I don't recall these being uber expensive so at 330k i think i would just go ahead and swap in new ones.

 

[cvenom96]

Another consideration would be oil leaks. That can really destroy a bushing/mount if they've been soaking in it for years.

 

[South Texas 97]

Good feedback, they have indeed had quite a bit of oil soaking over the years. I have done some cleaning to see where the leaks are coming from.

 

[flintknapper]

Good feedback, they have indeed had quite a bit of oil soaking over the years. I have done some cleaning to see where the leaks are coming from.

Until you get them out...it is difficult to assess them. Mine (at 316K, also a Texas Truck) were in need of replacement. I was chasing a small vibration (mostly at idle) that I just couldn't seem to find a reason for. Usually it will be the Driver's side mount that is separating, but do both of them and the Trans/Tcase mount.

 

[Feistl]

If you are replacing the mounts, is it worth going genuine or is after market ok?

I know with some hydraulic filled mounts going OEM is worth it, but if this is just a block of rubber would you notice a difference?

 

[flintknapper]

If you are replacing the mounts, is it worth going genuine or is after market ok?

I know with some hydraulic filled mounts going OEM is worth it, but if this is just a block of rubber would you notice a difference?

OEM or a reputable aftermarket supplier. ALL rubber is NOT the same. You buy Chinese junk for this project and you'll be doing it again sooner than you want.

 

[White Sheep]

I replaced mine at 150K. @NLXTACY recommended it as I was prepping for his turbo. He said it was one of the things he wished he'd done. The transmission mount wasn't bad (decent shape and easy replacement). The motor mounts were a bitch and needed to be replaced. Damn near jacked the motor out of the engine bay to get enough space to take out and replace. Others claim to of had an easier time.

 

[flintknapper]

I replaced mine at 150K. @NLXTACY recommended it as I was prepping for his turbo. He said it was one of the things he wished he'd done. The transmission mount wasn't bad (decent shape and easy replacement). The motor mounts were a bitch and needed to be replaced. Damn near jacked the motor out of the engine bay to get enough space to take out and replace. Others claim to of had an easier time.

Yeah. Same for me.......(Screaming B***h of a job).

I can't imagine what set of circumstances could possibly make this easier one vehicle to the next.

One thing I found helpful when installing the new ones was to cut about 3/16" off the length of the studs (which are longer than needed anyway).

Even then..... getting the locating tab lined up in the slot.....etc, etc....was a chore. I just walked away from it one afternoon late and finished up the next day after I had settled down.

Hard to see what you are doing when the veins are standing out on your neck and blood is squirting from your eyes. Hated that job. It fought me from the get-go (and won handily the first day).

 

[Kernal]

And while you're in there check the engine mount brackets where they attach to the frame for cracks; found one of mine with a hairline crack almost the full length of the original weld line. The crack was very hard to see, sprayed penetrating oil on the top of the crack to see if it showed up underneath (by going through the crack). Had it welded by a certified welder at a Toyota dealer who had their own full service Collision/Body shop.

Hairline vertical crack in center of photo looked almost like a shadow:

Pick pointing to crack:

Weld repair of crack:

 

[South Texas 97]

Exactly the feedback I was looking for, thanks to all. Will let you know the outcome, with photos of course!

 

[Heckraiser]

I did my upper oil pan re-seal project and really should have done the motor mounts at that time because the oil pan project gets you most of the way there (engine unbolted and jacked up). But I'm a lazy turd, so I didn't do it.

If your upper oil pan arch is leaking, it would be smart to do both at the same time. Oil pan project sucks though, be warned!

 

[South Texas 97]

Thanks Heckraiser, after all my under frame cleaning, I think that may be where my leak is coming from.