Advice for my fixed (but not cured) tranny (i'm gonna to kill it)

[monochamus]

As many of you know, I took my XC to the mechanic to fix the tranny (harsh shifts and bumpy D and R)

So, the guy made a deficient work: rebuild the gearbox and replace the valve body, but not the solenoids, he kept the old ones from the former V/B. And put on it dex-merc atf (or maybe mercon v). He was a complete ignorant.

The guy called me to take out the car from the shop, he said "the job is done".
So I drove the car back to home (380 miles) and the gearbox had an harsh 5-4 downshift, but increased in uphills , like a bang. the thing went worse pushing to pass heavy trucks and the 5-4 downshift felt like a huge drumroll. I can't affirm if the gearbox made the downshift.
All those stories were back in november 2014.
A month ago, I did a complete flush (gibbons method-12qt- T-t IV) and the car shifts much better, smooth through all gears, but the "drumroll" in 5th to 4th downshift is still there. It appears when downshifts in uphill roads.
So here is the question: i don't know if this issue is due an a faulty valve body (and the solenoids mixed) or if it is something else.
Can a Seafoam transtune fix my trouble?
Your wisdom will be appreciated.
Thanks as always
Gracias amigos!!

[howardc64]

If Type IV ATF made shifts smoother, then previous ATF fill was most likely the wrong type.

You mentioned the mechanic reused the solenoids, did he rebuild the 3 linear solenoids? If not, then some shift problems likely persist.

Doubt seafoam transtune will do anything for your gearbox.

[monochamus]

You mentioned the mechanic reused the solenoids, did he rebuild the 3 linear solenoids?

Rebuild? I don't think so... He didn't say anything about that.
Howard, hoy many solenoids has the valve body?
Thanks again pal!

[perkinscl]

What do you mean by "drumroll, when shifting down from 5th to 4th"?

[monochamus]

What do you mean by "drumroll, when shifting down from 5th to 4th"?
Shudder/ heavy vibration in downshift

[howardc64]

how many solenoids has the valve body?


http://www.valvebodybuilders.com/nissan_re5f22a_aw55_50sn.jpg

5 on/off solenoids (S1-S5). These have only 2 positions on/off (or open/close) so the amount pressure controlled by these solenoids will only have 2 settings. When these fail, I think you generally lose some gears.

3 Linear solenoids (SLT, SLS, SLU). These allow variable amount of fluid flow so they control variable amount of pressure. When these are worn, pressure can't be controlled very well and you get hard shifts or delay shifts.

The effort required to rebuild a tranny should have at least included replacing or recondition/rebuilding the solenoids. Especially the linear ones which is one of the high failure rate items on this valvebody. If your mechanic didn't do these (and likely put in the wrong ATF), I'd be concerned quality of the overall rebuild.

[monochamus]

http://www.valvebodybuilders.com/nissan_re5f22a_aw55_50sn.jpg

5 on/off solenoids (S1-S5). These have only 2 positions on/off (or open/close) so the amount pressure controlled by these solenoids will only have 2 settings. When these fail, I think you generally lose some gears.

3 Linear solenoids (SLT, SLS, SLU). These allow variable amount of fluid flow so they control variable amount of pressure. When these are worn, pressure can't be controlled very well and you get hard shifts or delay shifts.

The effort required to rebuild a tranny should have at least included replacing or recondition/rebuilding the solenoids. Especially the linear ones which is one of the high failure rate items on this valvebody. If your mechanic didn't do these (and likely put in the wrong ATF), I'd be concerned quality of the overall rebuild.

What amount of knowledge Howard! Really thanks for your info.
By the way, I have another question : which pieces on the gearbox can make a squeaky noise? is another symptom that I have :(