2004 5.3 into a 1998 K1500 keeping 1998 4L60e

[bmiller]

I'm going to apologize before I even begin. I'm a lifelong mechanic with scads of experience with old (40s-90s) cars with modification, but only repairs on newer vehicles. I'm searched far and wide and it's possible I'm not using the correct terms.

My customer is having me swap a 2004 GMC 5.3 into his 1998 Chevy K1500 and he wants to use his original 4L60e transmission.

I think i have a decent handle on everything except the transmission. I'm confident the transmission will bolt up minus the top bolt.

The questions I have are:

1. I'll need to retain the original shift computer? In the online interchanges I have seen it listed both ways. The tuner that's removing VATS advised me to use the 2004 truck engine side which has the transmission wiring attached. He advised me to use the LS computer to run it. One online interchange said both transmissions are wired identically. Next online interchange said that the 2004 transmission uses one plug for control while the 1998 transmission uses 2?

2. Will the torque convertor bolt up? In Oreilly's and other parts listings they show the convertor being 5 bolt in 1998, and the 5.3 I pulled is 3 bolt. The online videos show them all being 3 bolt. The input shafts also appear to be a different size, so I would assume I have to use the 1998 convertor? I'm guessing I use the stock 5.3 flexplate and the stock 1998 5.7 convertor?

3. Is there any spacers/bushings I need to buy? I've also seen this answered both ways. One guy says I need a bushing, but the next guy says only for turbo 400/350. Next guy said only on a 6.0.

I'm sorry as these questions I'm sure have been asked a hundred times.

Thanks for any help.

 

[NickTransmissions]

I'm going to apologize before I even begin. I'm a lifelong mechanic with scads of experience with old (40s-90s) cars with modification, but only repairs on newer vehicles. I'm searched far and wide and it's possible I'm not using the correct terms.

My customer is having me swap a 2004 GMC 5.3 into his 1998 Chevy K1500 and he wants to use his original 4L60e transmission.

I think i have a decent handle on everything except the transmission. I'm confident the transmission will bolt up minus the top bolt.

The questions I have are:

1. I'll need to retain the original shift computer? In the online interchanges I have seen it listed both ways. The tuner that's removing VATS advised me to use the 2004 truck engine side which has the transmission wiring attached. He advised me to use the LS computer to run it. One online interchange said both transmissions are wired identically. Next online interchange said that the 2004 transmission uses one plug for control while the 1998 transmission uses 2?

2. Will the torque convertor bolt up? In Oreilly's and other parts listings they show the convertor being 5 bolt in 1998, and the 5.3 I pulled is 3 bolt. The online videos show them all being 3 bolt. The input shafts also appear to be a different size, so I would assume I have to use the 1998 convertor? I'm guessing I use the stock 5.3 flexplate and the stock 1998 5.7 convertor?

3. Is there any spacers/bushings I need to buy? I've also seen this answered both ways. One guy says I need a bushing, but the next guy says only for turbo 400/350. Next guy said only on a 6.0.

I'm sorry as these questions I'm sure have been asked a hundred times.

Thanks for any help.

He won't be able to use his original 4L60E transmission that was paired w/the 1998 Vortec small block chevy motor without modifying the transmission to conform to the SBC convention or making a custom converter that will allow the 1998 unit to be paired with the 5.3 (And I am not versed on this mod, never having done it but perhaps others can provide specific details)...If going that latter route, you'll need a torque converter builder to make the converter to work with the LS engine and Gen1 SBC-pattern 4L60E.

Otherwise, the 4L60E will need to have the LS bell housing, torque converter, 300mm input shaft/fwd drum assembly, LS 7.25" pump stator swapped for the 298mm drum and 6.75" pump stator. To do all that work means you're rebuilding the entire transmission because there isn't much more in the way of work effort to overhaul the unit entirely, given how much has to come out just to swap those parts.

The simplest transmission solution is to have a Gen3 compatible 4L60E built then bolted up to the 5.3L. The transmission control logic was the same from 1996-2006 so programming shouldn't be an issue between the two different versions of 4L60E if running factory computers. The engine mgmt is another matter...

Re the manual lever position sensor which is bolted to the driver side of the transmission, over the selector shaft (Referred to #1 in your post) - 1995-2003 was a dual plug while 2004-2008 was a large, single plug.

 

[bmiller]

He won't be able to use his original 4L60E transmission that was paired w/the 1998 Vortec small block chevy motor without modifying the transmission to conform to the SBC convention or making a custom converter that will allow the 1998 unit to be paired with the 5.3 (And I am not versed on this mod, never having done it but perhaps others can provide specific details)...If going that latter route, you'll need a torque converter builder to make the converter to work with the LS engine and Gen1 SBC-pattern 4L60E.

Otherwise, the 4L60E will need to have the LS bell housing, torque converter, 300mm input shaft/fwd drum assembly, LS 7.25" pump stator swapped for the 298mm drum and 6.75" pump stator. To do all that work means you're rebuilding the entire transmission because there isn't much more in the way of work effort to overhaul the unit entirely, given how much has to come out just to swap those parts.

The simplest transmission solution is to have a Gen3 compatible 4L60E built then bolted up to the 5.3L. The transmission control logic was the same from 1996-2006 so programming shouldn't be an issue between the two different versions of 4L60E if running factory computers. The engine mgmt is another matter...

Re the manual lever position sensor which is bolted to the driver side of the transmission, over the selector shaft (Referred to #1 in your post) - 1995-2003 was a dual plug while 2004-2008 was a large, single plug.

Thanks you for the info.

I'm going to advise my customer to go another route or get out his checkbook.

Thanks again

 

[NickTransmissions]

Thanks you for the info.

I'm going to advise my customer to go another route or get out his checkbook.

Thanks again

You're welcome...If you or he can obtain a good, used 4L60E *this is a gamble* he can perhaps sell his current 4L60E, if that's blowing the budget and ends up costing you the job.

 

[el torro]

He could go with a Holly transmission controller, LS carburetor intake, and a Holly EFI Sniper kit. I think Holly makes a module to make it all work with the factory gauges. I’m in the very early information gathering stage to LS swap a 98 c3500. I want to try and save the transmission this in the truck and have it rebuilt so I’m looking at things that would make it an easier swap. My personal solution for the gages is going to replace them with an aftermarket set.

 

[NickTransmissions]

He could go with a Holly transmission controller, LS carburetor intake, and a Holly EFI Sniper kit. I think Holly makes a module to make it all work with the factory gauges. I’m in the very early information gathering stage to LS swap a 98 c3500. I want to try and save the transmission this in the truck and have it rebuilt so I’m looking at things that would make it an easier swap. My personal solution for the gages is going to replace them with an aftermarket set.

The problem isnt the command and control - that's an easy issue to solve for. The problem is the physical and dimensional differences in between the Gen1 and Gen3 small blocks and their respective 4L60Es that stand in the way of an easy swap.

In your case, the 4L80E in the C3500 will mate to a Gen3 LS as-is since the 4L80E never underwent the same component changes when GM went to the Gen3 engine family like the 4L60Es did.

Bell housing, input shaft, pump, flex plate, torque converter all changed in the 60Es for Gen3 engines.

 

[el torro]

The problem isnt the command and control - that's an easy issue to solve for. The problem is the physical and dimensional differences in between the Gen1 and Gen3 small blocks and their respective 4L60Es that stand in the way of an easy swap.

In your case, the 4L80E in the C3500 will mate to a Gen3 LS as-is since the 4L80E never underwent the same component changes when GM went to the Gen3 engine family like the 4L60Es did.

Bell housing, input shaft, pump, flex plate, torque converter all changed in the 60Es for Gen3 engines.

After I read your reply and then reread the original post I caught on to the original question. That's what I get when posting a reply right before bed. Thank you for the info on my 4L80E, not having to source a new transmission *should* help with the overall cost. I plan on rebuilding/upgrading it when I do the swap.

 

[NickTransmissions]

After I read your reply and then reread the original post I caught on to the original question. That's what I get when posting a reply right before bed. Thank you for the info on my 4L80E, not having to source a new transmission *should* help with the overall cost. I plan on rebuilding/upgrading it when I do the swap.

No worries, man...I get myself into trouble responding to forum posts without my required coffee in the morning and answer questions that weren't even asked, lol.