How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Gary Your Own Question
Gary, Technician
Category: Car
Satisfied Customers: 16742
Experience:  GM master tech for 15 years/ASE master tech for 20 years
Type Your Car Question Here...
Gary is online now
A new question is answered every 9 seconds

Isuzu Trooper: OK here goes. 2002 Isuzu Trooper transmission

This answer was rated:

OK here goes. 2002 Isuzu Trooper transmission question. Gm 4l30e trans w/ pwm. At low rpm, generally around 1500, and light load get an intermittent "brrrrrr" sound. More so when trans is cold. If I take my foot off the gas it stops. Might start again might not. when I engage power mode which holds trans in gear longer so higher rpm not as prevalent. From what I've been able to find think it has to do with the tcc cycling and not fully engaging, might be tcc solenoid. Thoughts?

Welcome! My name is XXXXX XXXXX I will do my best to assist you with this problem.

im sorry your having this problem

so this problem has been there for a long time even before old transmission was rebuilt ?

your old one was rebuilt correct? not replaced with a new one ?

do you know if there are any codes in the computer ?

and it seems to do this when the TCC locks up into over drive and if you kick it down with the gas pedal the noise will go away ?


Customer: replied 3 years ago.

yes, problem was there before rebuild (not replacement)


haven't had codes pulled yet, that's my next step


not when in overdrive, typically 30-40 mph, 1500+/- rpm


had my mech check driveline, bearings etc. could not find any other problems

is it a matter of it seems to be shifting too quick into the next gear and almost lugging the engine down ?

similar to if you are driving a stick shift and upshift to next gear too early and it drags the engine down so to say ?

Customer: replied 3 years ago.

no, sometimes sound is loud other times not so much, rpm jump a little when this happens and can fell it through the pedal. sounds like its coming from trans area under the shifter. happens more when its cold not as bad when trans warms up. intermittent so when I took it in to my mech it would not do it. from research online sounded like its the tcc cycling but not engaging could be bad tcc solenoid or pump pressure too low


Frank low pressure would cause slipping of the gears

it can be tcc chatter but only when its in tcc lock up with is over drive unless the tcc is being applied when it should not be

since it was doing this before that rules out a few things

Frank lets start slow with this lets first have the computer scanned for any codes in the computer history or current

any Pep Boys or Auto Zone will scan for free and tell you any code numbers

these computers are always monitoring the transmissions tcc and shaft speeds and if the tcc was not fully applying or usually if anything was not doing as it should electrically in the transmission


Customer: replied 3 years ago.

here is a link to a similar problem


how do I get back in touch after I've had codes pulled?

Frank you can always get me right back through this post any time with any follow up with this problem even after you rate us here at Justanswer !

Frank if there are no codes the next step is to monitor transmission live data with a scan tool when its acting up to see what the slip speed is reading and the TCC

this is tough as the TCC should only be locking up and applied when its going into over drive

also with the scan tool they can lock up the convertor with the scan tool and see if when they start locking it up by % increments if it will make that noise when they keep applying the TCC and what % they command it does this

I read the post and the issue I have with most of that vehicles issues is the transmission you have is yours is not slipping and the tach jumping showing the convertor was slipping from running this with 2 quarts low of fluid

this can be the torque convertor itself causing the brrrr noise

when rebuilt did a new convertor be installed ?

Customer: replied 3 years ago.


the post was not me but a similar situation

new tc was installed with rebuild


so maybe not the tcc could it be the transfer case?


yes it can be

will it do this in 4HI ?


Customer: replied 3 years ago.

don't run Torque on Demand (TOD-4hi) often so not sure

Frank check for codes first

then see if the noise will be there 4HI

Gary and 5 other Car Specialists are ready to help you