1 - 2 Shift Shudder when in Tow/Haul mode
12-14-2013, 07:28 PM
#1
12 Second Club
Thread Starter
iTrader: (5)
Join Date: May 2008
Location: Georgetown, Texas
Posts: 322
Likes: 0
Received 0 Likes
on
0 Posts
1 - 2 Shift Shudder when in Tow/Haul mode
Like the title says. Went to tow a trailer today I noticed in tow/haul mode it shudders pretty bad between the 1-2 shift. Only does it with on tow/haul mode. Trailer or no trailer.
Anyone have any ideas?
Thanks,
D
Anyone have any ideas?
Thanks,
D
12-21-2013, 02:02 PM
#3
I have a 99 and installed a shift kit in my old 4l60 and it would do the same thing. I got a 4l60 from performabuilt and didn't have to use the tow/haul again. I also had my ecu re flashed at the dealer and it eliminated the tow/haul option. I believe it has something to do with the increased line pressure and the way it modifies the shift points.
12-21-2013, 03:18 PM
#4
TECH Apprentice
Join Date: Jul 2009
Location: Hell
Posts: 397
Likes: 0
Received 0 Likes
on
0 Posts
If the shudder is excessive, yet it's not a transmission issue, I would take a look at the condition of your transmission/transfer case mount (if applicable).
My 4L80E is stuck with safety default shift pressures and shift points, because I have a wobbly rear output which was screwing up my VSS, so I pulled the plug off and now it shifts just like it tow/haul mode.
It was rough at first, but only made worse by the quickly deteriorating trans. mount. I replaced it with a cheap anchor brand version, which is soft and still allows a lot of flex, but is worlds better than a worn mount.
(BTW, My transfer case rebuild came in the mail this week, just waiting for the shop to clear up so I can fit my truck in and fix it).
My 4L80E is stuck with safety default shift pressures and shift points, because I have a wobbly rear output which was screwing up my VSS, so I pulled the plug off and now it shifts just like it tow/haul mode.
It was rough at first, but only made worse by the quickly deteriorating trans. mount. I replaced it with a cheap anchor brand version, which is soft and still allows a lot of flex, but is worlds better than a worn mount.
(BTW, My transfer case rebuild came in the mail this week, just waiting for the shop to clear up so I can fit my truck in and fix it).
12-22-2013, 08:37 PM
#5
12 Second Club
Thread Starter
iTrader: (5)
Join Date: May 2008
Location: Georgetown, Texas
Posts: 322
Likes: 0
Received 0 Likes
on
0 Posts
I have a 99 and installed a shift kit in my old 4l60 and it would do the same thing. I got a 4l60 from performabuilt and didn't have to use the tow/haul again. I also had my ecu re flashed at the dealer and it eliminated the tow/haul option. I believe it has something to do with the increased line pressure and the way it modifies the shift points.
If the shudder is excessive, yet it's not a transmission issue, I would take a look at the condition of your transmission/transfer case mount (if applicable).
My 4L80E is stuck with safety default shift pressures and shift points, because I have a wobbly rear output which was screwing up my VSS, so I pulled the plug off and now it shifts just like it tow/haul mode.
It was rough at first, but only made worse by the quickly deteriorating trans. mount. I replaced it with a cheap anchor brand version, which is soft and still allows a lot of flex, but is worlds better than a worn mount.
(BTW, My transfer case rebuild came in the mail this week, just waiting for the shop to clear up so I can fit my truck in and fix it).
My 4L80E is stuck with safety default shift pressures and shift points, because I have a wobbly rear output which was screwing up my VSS, so I pulled the plug off and now it shifts just like it tow/haul mode.
It was rough at first, but only made worse by the quickly deteriorating trans. mount. I replaced it with a cheap anchor brand version, which is soft and still allows a lot of flex, but is worlds better than a worn mount.
(BTW, My transfer case rebuild came in the mail this week, just waiting for the shop to clear up so I can fit my truck in and fix it).
D
Thread
Thread Starter
Forum
Replies
Last Post