[mikecm]

2007 S, 158k
About a week ago I drive to a doctor's appointment (roughly 10 city miles), truck runs perfectly normal. Go to back out of the parking spot and reverse doesn't want to engage, just kind of revs and sputters, eventually engages. Everything else seems fine until I'm almost home. Going through an intersection from a complete stop, truck hardly has any power in first gear, not completely dead just rough. Bit of a jerk into second and seems fine from there.

Parked for two days while I research the problem. Go to take it around the block, reverse engages no problem. First gear is fine at first. Round the corner and first gear gets real rough again and loses all acceleration, just revs.

Parked for another two days. Against my better judgment, I decided to try and get it to the cleaners just down the road so I can get it posted to sell. Reverse is fine. Goes into first through third. This time though, I notice a whirring/buzzing noise coming from underneath while the accelerator is pushed which has never happened and it doesn't seem like the timing chain humming. Once back down to first, it loses all acceleration and just revs. Coast into a parking lot and turn it off. Sit a minute, crank back up and goes into gear. I'm lock two blocks away from home so I basically just coast back.

I've been scouring the internet and trying to diagnose what I can with what little knowledge and resources have.
No knock or any other noises besides the buzzing.
It's not SMOD. Transmission fluid is a little dark but not milky or low and no residue under the radiator cap.
No codes are being thrown except for the fuel censor (it's been out for a while, just haven't had time to drop the tank and replace).
Not running hot, has full tank of gas, and oil is fine.
Crankshaft position sensor died and was replaced last year.

Sorry for the long OP but if you made it this far, thank you. What do you guys think? Would somewhat old transmission fluid cause this much of a problem? Could it be another sensor somewhere even though I don't have a code for it? Solenoids? I'm running in circles and don't have money to just throw at a shop in hopes they figure it out.

 

[XT2015]

2007 S, 158k
About a week ago I drive to a doctor's appointment (roughly 10 city miles), truck runs perfectly normal. Go to back out of the parking spot and reverse doesn't want to engage, just kind of revs and sputters, eventually engages. Everything else seems fine until I'm almost home. Going through an intersection from a complete stop, truck hardly has any power in first gear, not completely dead just rough. Bit of a jerk into second and seems fine from there.

Parked for two days while I research the problem. Go to take it around the block, reverse engages no problem. First gear is fine at first. Round the corner and first gear gets real rough again and loses all acceleration, just revs.

Parked for another two days. Against my better judgment, I decided to try and get it to the cleaners just down the road so I can get it posted to sell. Reverse is fine. Goes into first through third. This time though, I notice a whirring/buzzing noise coming from underneath while the accelerator is pushed which has never happened and it doesn't seem like the timing chain humming. Once back down to first, it loses all acceleration and just revs. Coast into a parking lot and turn it off. Sit a minute, crank back up and goes into gear. I'm lock two blocks away from home so I basically just coast back.

I've been scouring the internet and trying to diagnose what I can with what little knowledge and resources have.
No knock or any other noises besides the buzzing.
It's not SMOD. Transmission fluid is a little dark but not milky or low and no residue under the radiator cap.
No codes are being thrown except for the fuel censor (it's been out for a while, just haven't had time to drop the tank and replace).
Not running hot, has full tank of gas, and oil is fine.
Crankshaft position sensor died and was replaced last year.

Sorry for the long OP but if you made it this far, thank you. What do you guys think? Would somewhat old transmission fluid cause this much of a problem? Could it be another sensor somewhere even though I don't have a code for it? Solenoids? I'm running in circles and don't have money to just throw at a shop in hopes they figure it out.

Does the transmission fluid have a burnt smell to it? When was it last changed that you know of?

 

[mikecm]

Does the transmission fluid have a burnt smell to it? When was it last changed that you know of?

Maybe a bit. It's hard to say for certain as I don't have anything to compare it to. I bought it with around 125k, it looked good then and I haven't changed it since I've had the truck. Would that indicate something inside the transmission burning out?

I've explained everything to a few shops and I've only had one recommend a transmission and radiator replacement for $6k. Another called back claiming they couldn't find a replacement but offered to buy it for themselves, which I thought was kinda sketch

 

[XT2015]

Maybe a bit. It's hard to say for certain as I don't have anything to compare it to. I bought it with around 125k, it looked good then and I haven't changed it since I've had the truck. Would that indicate something inside the transmission burning out?

I've explained everything to a few shops and I've only had one recommend a transmission and radiator replacement for $6k. Another called back claiming they couldn't find a replacement but offered to buy it for themselves, which I thought was kinda sketch

Both those proposals are surely suspect. Light red to pink color is like new. A burnt smelling fluid has been cooked and most of the important chemistry in the fluid that is required for proper performance has been burnt off. Having the transmission fluid fully flushed and replaced with the proper spec fluid is not an expensive gamble. New fluid can work wonders if the damage hasn't progressed to the physical stage internal to the transmission.

 

[mikecm]

Both those proposals are surely suspect. Light red to pink color is like new. A burnt smelling fluid has been cooked and most of the important chemistry in the fluid that is required for proper performance has been burnt off. Having the transmission fluid fully flushed and replaced with the proper spec fluid is not an expensive gamble. New fluid can work wonders if the damage hasn't progressed to the physical stage internal to the transmission.

I was hesitant to do it at first because I'm so broke and didn't want it to go to waste but I'll likely be doing a drain and fill today.

I also tried getting TCU codes using this method I found posted in other Xterra threads but the O/D light just stayed on and didn't flash at all. I couldn't move the shift lever at all with the ignition in the acc position so I did every step with the shift lock release pressed in. I've done it several times and the light just stays on in the end.

 

[XT2015]

I was hesitant to do it at first because I'm so broke and didn't want it to go to waste but I'll likely be doing a drain and fill today.

I also tried getting TCU codes using this method I found posted in other Xterra threads but the O/D light just stayed on and didn't flash at all. I couldn't move the shift lever at all with the ignition in the acc position so I did every step with the shift lock release pressed in. I've done it several times and the light just stays on in the end.

You say it's not SMOD but here's the radiator listing that will allow you to check your radiator # to see if yours is a candidate for failure.
Here is the discussion and listing of the SMOD radiators: You are bypassed but know that your radiator is on the list.
According to CourtesyParts | Genuine OEM Nissan Parts & Accessories and other Nissan parts dealers, the following is the progression of OEM Calsonic radiators for the Xterra, with the years for each particular part number culled from TheNewX posts in brackets:

21410-EA200 [seldom referenced, but may have been installed in some very early 2005’s.]

21410-EA205 [2005 – either 2/09 or 8/09. Listed on some parts websites as P/N 21460-EA205. There is some confusion as to when these were used. Some literature states until 2/09 and other literature states 8/09. P/N IS ASSOCIATED WITH SMOD. ]

21460-EA215 [2005 - either 2/09 until 8/09, see above. Listed as discontinued and replaced by 21460-9CAOE on Nissan parts websites. P/N IS ASSOCIATED WITH SMOD]

21460-EA265 [production dates unknown other @Surf and Snow's Xterra built in 04/05 and my own Xterra built in 09/05. P/N IS ASSOCIATED WITH SMOD.]

21460-ZL11A [8/09 through 2010 model year, isolated reports of SMOD, however I have not been able to verify.]

21460-ZL31A [production dates unknown. Listed as discontinued on Nissan parts websites , no known reports of SMOD.]

21460-9CAOE [2011 – 2015 model years – no known reports of SMOD] This is the part number for the most current version as of 11/16.

 

[mikecm]

You say it's not SMOD but here's the radiator listing that will allow you to check your radiator # to see if yours is a candidate for failure.
Here is the discussion and listing of the SMOD radiators: You are bypassed but know that your radiator is on the list.
According to CourtesyParts | Genuine OEM Nissan Parts & Accessories and other Nissan parts dealers, the following is the progression of OEM Calsonic radiators for the Xterra, with the years for each particular part number culled from TheNewX posts in brackets:

21410-EA200 [seldom referenced, but may have been installed in some very early 2005’s.]

21410-EA205 [2005 – either 2/09 or 8/09. Listed on some parts websites as P/N 21460-EA205. There is some confusion as to when these were used. Some literature states until 2/09 and other literature states 8/09. P/N IS ASSOCIATED WITH SMOD. ]

21460-EA215 [2005 - either 2/09 until 8/09, see above. Listed as discontinued and replaced by 21460-9CAOE on Nissan parts websites. P/N IS ASSOCIATED WITH SMOD]

21460-EA265 [production dates unknown other @Surf and Snow's Xterra built in 04/05 and my own Xterra built in 09/05. P/N IS ASSOCIATED WITH SMOD.]

21460-ZL11A [8/09 through 2010 model year, isolated reports of SMOD, however I have not been able to verify.]

21460-ZL31A [production dates unknown. Listed as discontinued on Nissan parts websites , no known reports of SMOD.]

21460-9CAOE [2011 – 2015 model years – no known reports of SMOD] This is the part number for the most current version as of 11/16.

Mines on there and the previous owner hadn't dealt with it so it looks like I may be in danger. I saw where there was a campaign for the issue and Nissan was halving the cost if you weren't under warranty. Is that still a thing?

If it isnt SMOD, I suspect the transmission is clogged/blocked in some way or another. I did a drain and fill the other day, about 4 qts. Warmed up after filling and the reading was a bit high. Also, couldn't get any gear to engage. Let it sit over night, checked the next morning and this was the dip stick cold...

I was worried about only pulling 4qts because most other threads noted pulling at least 4.5 but the stick is still coming out like that and won't go into any gear.

 

[XT2015]

Mines on there and the previous owner hadn't dealt with it so it looks like I may be in danger. I saw where there was a campaign for the issue and Nissan was halving the cost if you weren't under warranty. Is that still a thing?

If it isnt SMOD, I suspect the transmission is clogged/blocked in some way or another. I did a drain and fill the other day, about 4 qts. Warmed up after filling and the reading was a bit high. Also, couldn't get any gear to engage. Let it sit over night, checked the next morning and this was the dip stick cold...
View attachment 80162
I was worried about only pulling 4qts because most other threads noted pulling at least 4.5 but the stick is still coming out like that and won't go into any gear.

Is this the dip stick cold with the engine running? Needs to be checked while running.

 

[mikecm]

Is this the dip stick cold with the engine running? Needs to be checked while running.

dead cold, just out of curiosity. It reads the same once it's warmed and running.

 

[XT2015]

dead cold, just out of curiosity. It reads the same once it's warmed and running.

Your picture above is showing the "Hot" reading side of the dip stick. If that's a cold reading then I expect you are over filled. Over filled is no good either. Over filling fluids generally cause air bubbles to form in the fluid and change the hydraulic characteristics of the fluid because the air component in the fluid compresses.

 

[mikecm]

Your picture above is showing the "Hot" reading side of the dip stick. If that's a cold reading then I expect you are over filled. Over filled is no good either. Over filling fluids generally cause air bubbles to form in the fluid and change the hydraulic characteristics of the fluid because the air component in the fluid compresses.

I suspected it was over as well but I only pulled like 3.8 quarts from the pan. The whining/buzzing noise is consistent in park now and I've concluded it's either a shot torque converter or the filter/screen is clogged and starving the transmission of fluid. I may drop the pan tomorrow to check the screen and try putting back a little less to see how it acts.

 

[XT2015]

I suspected it was over as well but I only pulled like 3.8 quarts from the pan. The whining/buzzing noise is consistent in park now and I've concluded it's either a shot torque converter or the filter/screen is clogged and starving the transmission of fluid. I may drop the pan tomorrow to check the screen and try putting back a little less to see how it acts.

Sounds like a plan.

I suspected it was over as well but I only pulled like 3.8 quarts from the pan. The whining/buzzing noise is consistent in park now and I've concluded it's either a shot torque converter or the filter/screen is clogged and starving the transmission of fluid. I may drop the pan tomorrow to check the screen and try putting back a little less to see how it acts.

You should be suspicious of the transmission fluid having to pass through the "SMOD" radiator cooling passage and maybe the restriction is being created there as the radiator failure is starting to materialize internal to the radiator. I would look seriously into replacing the radiator or doing the "bypass" cooling line procedure that is documented elsewhere on this site as part of the SMOD discussion. You absolutely don't want the coolant to mix in with the transmission fluid.

 

[MeToo]

Also, if you elect to do the bypass where the trans fluid no longer touches the radiator itself, then take the 2 cooler lines coming out of the rad and clamp a hose on them so that they have no chance of leaking coolant all over the ground if the trans cooler inside springs a leak.

'Cuz if it duz, you'll have green or orange goo on the ground!
And you'll play the Dickens trying to drive it around.

(Lyrics above are trademarked, patented, registered, and useless.)

 

[DickyDck]

I have 2 Xterra, an 06 and an 07, both bought with SMOD issues. Your symptoms all sound like SMOD with its slow creep of death leaving you stuck somewhere on the side of the road. Hoping this isn’t the case for you brother, unless you are pretty mechanically inclined a fix would cost you several thousand dollars in parts and labor.