NTB08-045

[NissanTech]

A new entry has been added to Knowledgebase

Description:

2008 NISSAN PATHFINDER, RONTIER, XTERRA;

SHORT BUMP/THUMP FELT DURING LIGHT ACCELERATION

A short-lasting (less than 1 second) bump/thump is felt:
• With light throttle application (slight throttle tip-in, less than 2/8)
and
• while driving on a flat or slightly inclined road
and
• with the transmission in fith gear and torque converter at full lockup
and
• with an engine speed of approximately 1100-1300 RPM
and

• at speeds of 35-45 MPH.

To check it out, rate it or add comments, visit NTB08-045
The comments you make there will appear in the posts below.

[minan]

If you come off the gas or lightly tap the gas at low speeds i get the thump.
It sounds like a major drive train or u joint problem

[Atcguy]

I have this EXACT problem. I've mentioned it to the dealer about 5 times during oil changes. They say it's normal operation. My last truck did the same thing before the rear diff failed.
I suppose I'll print the TSB and tell them my '07 OR seems to be doing what the bulletin describes. Is no one else with a 06, 07, etc. getting this issue?

[sb8376]

Based on the rpm, ground speed, lockup and so on, this could be a downshift or falling out of overdirve lockup condition. This situation is why an overdrive lockout is provided on the shifter. If you constantly operate your vehicle in this driving range, you should press the button to keep the torque converter from full lockup. A slow gentle acceleration on level or slight downward slope will find the transmission getting into overdrive near 40 mph (the 35 - 45 mph range mentioned). When the throttle is lifted the vehicle remains in OD until more torque condition is signalled by slightly depressing the throttle. This causes the transmission to seek a lower gear and either shift out of OD or downshift.

[sb8376]

Originally Posted by sb8376

Based on the rpm, ground speed, lockup and so on, this could be a downshift or falling out of overdirve lockup condition. This situation is why an overdrive lockout is provided on the shifter. If you constantly operate your vehicle in this driving range, you should press the button to keep the torque converter from full lockup. A slow gentle acceleration on level or slight downward slope will find the transmission getting into overdrive near 40 mph (the 35 - 45 mph range mentioned). When the throttle is lifted the vehicle remains in OD until more torque condition is signalled by slightly depressing the throttle. This causes the transmission to seek a lower gear and either shift out of OD or downshift.

[JnorXterra]

That's nice and all, but is no excuse for hearing and feeling the transmission thump. I've taken mine in twice for it. The second time they supposedly did the ECU update, but guess what? Still thumps. And even with the radio on low I can still hear it. This is this models what, 5th year? No excuse. And I'm not turning off OD every time I get off the highway. That's absurd.

Originally Posted by sb8376

Based on the rpm, ground speed, lockup and so on, this could be a downshift or falling out of overdirve lockup condition. This situation is why an overdrive lockout is provided on the shifter. If you constantly operate your vehicle in this driving range, you should press the button to keep the torque converter from full lockup. A slow gentle acceleration on level or slight downward slope will find the transmission getting into overdrive near 40 mph (the 35 - 45 mph range mentioned). When the throttle is lifted the vehicle remains in OD until more torque condition is signalled by slightly depressing the throttle. This causes the transmission to seek a lower gear and either shift out of OD or downshift.