[GMC Sierra 2018 SLT 2WD 5.8L FLEX] Hard shifting issue

[Areeb Mohamed]

Hi,

I have GMC Sierra 2018 SLT 2WD 5.3L FLEX 8 SPD,

There is a hard shifting issue occurs when shifting from 1st to 2nd gear and even when the truck is on the "P" occurring when the RPM going from 3000 - 4000 range.

I went to the dealer, They checked everything and they says we can't fix it unless we open the whole gearbox and that will costs around $500 and will takes some weeks to investigate.

Now i am currently in Iraq and really confused about this issue.

I hope you can help me by suggesting some workarounds and fixes.

 

Thanks

[LDM]

4 hours ago, Areeb Mohamed said:

Hi,

I have GMC Sierra 2018 SLT 2WD 5.3L FLEX 8 SPD,

There is a hard shifting issue occurs when shifting from 1st to 2nd gear and even when the truck is on the "P" occurring when the RPM going from 3000 - 4000 range.

I went to the dealer, They checked everything and they says we can't fix it unless we open the whole gearbox and that will costs around $500 and will takes some weeks to investigate.

Now i am currently in Iraq and really confused about this issue.

I hope you can help me by suggesting some workarounds and fixes.

 

Thanks

The dealer you are taking it to either doesn't want to do TSB 18-NA-355 or they don't know about it.  Either way, I would find another dealer.  I had the same 1-2 hard shift on my 18 Sierra, had my dealer perform the TSB and it fixed it immediately.  That was probably 8 months ago or so and haven't had the issue since.  I would go to another dealer, have them perform the TSB 18-NA-355, and you should be all set.

[Areeb Mohamed]

The problem is this the only 1 dealer in Iraq,

I went two times for investigation and they says we can't do anything to your truck, I was really disappointed.

Thank you for the information about this service bulletin, I will try to do it in an external workshop and let you know.

 

[LDM]

On 10/1/2020 at 3:18 AM, Areeb Mohamed said:

The problem is this the only 1 dealer in Iraq,

I went two times for investigation and they says we can't do anything to your truck, I was really disappointed.

Thank you for the information about this service bulletin, I will try to do it in an external workshop and let you know.

 

Yes, that could a be significant issue.  Didn't realize you were so limited in choice.  The TSB is for swapped out the old fluid that is very prone to absorbing water with the new Mobil HP LV fluid and a new transmission filter.  Anyone should be able to do it but the GM dealer is suppose to do it for free in the TSB.  The fluid is rather expensive and you will need at least 12 quarts for the entire transmission.

[Areeb Mohamed]

2 hours ago, LDM said:

Yes, that could a be significant issue.  Didn't realize you were so limited in choice.  The TSB is for swapped out the old fluid that is very prone to absorbing water with the new Mobil HP LV fluid and a new transmission filter.  Anyone should be able to do it but the GM dealer is suppose to do it for free in the TSB.  The fluid is rather expensive and you will need at least 12 quarts for the entire transmission.

Thanks for the information, 
Yes, After reading the service bulletin from this link 

https://static.nhtsa.gov/odi/tsbs/2019/MC-10163890-9999.pdf

 

It seems that only the dealer can perform these instructions,

But i've read in Page 3 - Point No. 1 that i will need 20 quarts !? Are you sure 12 quarts are enough ?

 

Thanks,

Areeb

[LDM]

22 minutes ago, Areeb Mohamed said:

Thanks for the information, 
Yes, After reading the service bulletin from this link 

https://static.nhtsa.gov/odi/tsbs/2019/MC-10163890-9999.pdf

 

It seems that only the dealer can perform these instructions,

But i've read in Page 3 - Point No. 1 that i will need 20 quarts !? Are you sure 12 quarts are enough ?

 

Thanks,

Areeb

I'm not 100% sure on the exact amount, 12 quarts is the bare minimum from what I have read.  But I also haven't done a full exchange on my truck as I had my dealer perform the TSB when I started getting the 1-2 hard shift.  GM uses a machine to do the flushing, so it probably does take 20 quarts.  If I was doing it a fluid exchange using the transmission cooler hose removal technique like I have on other vehicles I have owned, I would probably have at least 16 quarts on hand.  Better to have more than not enough.

[Areeb Mohamed]

3 minutes ago, LDM said:

I'm not 100% sure on the exact amount, 12 quarts is the bare minimum from what I have read.  But I also haven't done a full exchange on my truck as I had my dealer perform the TSB when I started getting the 1-2 hard shift.  GM uses a machine to do the flushing, so it probably does take 20 quarts.  If I was doing it a fluid exchange using the transmission cooler hose removal technique like I have on other vehicles I have owned, I would probably have at least 16 quarts on hand.  Better to have more than not enough.

Cool, Do you recommend any online store in US that selling Mobil HP LV fluid with good price ?

[LDM]

1 hour ago, Areeb Mohamed said:

Cool, Do you recommend any online store in US that selling Mobil HP LV fluid with good price ?

When I was looking at the beginning of the year in case I had to do it myself, the best prices I found were on Ebay.  Not sure if they will ship to Iraq or if it would be cost efficient but its worth a look.  Amazon had it too, as well as Summit Racing and Jegs but the price was a bit higher.  Its definitely a pricey ATF, most of the stuff on Ebay is $70 for 6 quarts.  Regular Dex VI is only around $20 for a gallon (4 quarts), which of course we can't use in the 8 speed transmission.  I don't know much about Iraq when it comes to auto parts stores but they don't even stock this ATF at places like Advance Auto, Autozone, or NAPA, so you are pretty much stuck ordering online or getting it from a dealer.

[Areeb Mohamed]

4 minutes ago, LDM said:

When I was looking at the beginning of the year in case I had to do it myself, the best prices I found were on Ebay.  Not sure if they will ship to Iraq or if it would be cost efficient but its worth a look.  Amazon had it too, as well as Summit Racing and Jegs but the price was a bit higher.  Its definitely a pricey ATF, most of the stuff on Ebay is $70 for 6 quarts.  Regular Dex VI is only around $20 for a gallon (4 quarts), which of course we can't use in the 8 speed transmission.  I don't know much about Iraq when it comes to auto parts stores but they don't even stock this ATF at places like Advance Auto, Autozone, or NAPA, so you are pretty much stuck ordering online or getting it from a dealer.

Actually, It's not available in Iraq, Even the in the dealer's store.

We are using a mail forwarding service called "MyUS" which is a warehouse in FL, Then i can purchase any items from any US based websites and send it directly to the forwarder's address and they will send it directly to Iraq via DHL or FedEx. 

 

Thanks a lot for your valuable information, You have really saved me and saved my wallet